Eligibility to write TGT/PGT with B.Ed+BE qualification

You are interested to take up two courses simultaneously as you have indicated that you want to take up M.A in Economics apart from your present continuation of B.Ed.. However you should ensure that both the courses should not be of the regular mode. If you are doing B.Ed in regular mode , the other course - M.A. ( Economics)should be followed by the distance education.
Now coming in terms of your writing in PGT in Economics, you can do the same if you have a flair for Economics. You would be selected provided you do better in the PGT test both in the written and the oral test conducted by the experts of the selection team.

Once you complete your B.Ed you will be eligible to write the teacher entrance test. You have to get qualified for the entrance test that will be conducted by the concerned authorities. These tests will be conducted at the state level or district level based on the available vacancies.
The second question is doing MA Economics simultaneously, it is possible to do that. One course you can do in regular mode and the other in distance education mode. I think you are doing B.Ed in regular mode. You can do MA in distance mode. If you clear your MA with a minimum of 50% marks, you will become eligible to write the PGT test for economics after completing both MA and B.Ed.
Many universities are offering MA courses in distance mode. You can select any university based on your convenience and place of residence.

As you said that you have completed BE (Civil) and now you are doing B.Ed in Mathematics and Physics, then the first thing is that after doing B.Ed. you will be able to make a career as a government teacher. There will be no hindrance. With this, the answers to your various questions are as follows -

1. If I complete MA (Economics), are you eligible for government teaching jobs - as you said, till now only your graduation is complete i.e. you are fully eligible for post-graduation but at least 50% marks in your graduation Ho. When you complete your postgraduate degree in Economics, you have the possibility of the following teaching government job -

- For Professor or Lecturer - both you can apply in any college or university. Well, for this you can start your practice as a guest teacher after some exams if you want from MA.
- Coaching teachers - This is currently a great option, many people prepare for the government exams, and various institutes often lack a good economy teacher as economics is a tricky subject and very few people have good knowledge, If you are interested in economics, then you can groom many such children. In many places in Delhi, Indore, Gwalior, there is a demand for such teachers in abundance.

2.Eligible for writing PGT (Economics) and other exams - Yes you can definitely take the PGT exam, as post-graduation in Economics, you can participate in both PGT and TGT exam in the same year. One piece of advice for you is to start preparing for PGT with your postgraduate studies so that you can save your time later.

3.Can do B.ed and MA simultaneously- Yes, if you are capable and comfortable, you can do both courses simultaneously.
But my advice is since both courses are very hard subjects and courses in their own way, doing so can cause a bit of trouble for you as well. If you had only one subject then you would still have got it easy, but your B.Ed. the subject is mathematics and you want to take economics in mother. It may be a bit complicated, but take the final decision with your discretion.

4. Regarding CTET exam- Applicants for CTET should have the following qualifications -
Has a bachelor's degree and has passed or passed the final year examination of Diploma in Elementary Education.
Or have completed Bachelor's degree with 50% marks and have been appearing or have passed the final year examination in Bachelor of Education.

Generally for being eligible to applying for PGT positions one has to have a Master's Degree from a recognised university with at least 50% marks in aggregate in the concerned subject and that holds good for the subject Economics also. After this only one can apply or participate in the entrance examination conducted by agencies like Kendriya Vidyalaya etc. Another condition is that one must have a B.Ed or equivalent degree from a recognised University. In addition to above two criterion one should be proficient in teaching in Hindi and/or English Medium.

For TGT teaching positions one has to have a Bachelor's Degree with at least 50% marks in the concerned subject/combination of subject and in aggregate. The candidate should also have a B.Ed or equivalent degree from a recognised University. Another requirement is that one must qualify in Central Teacher Eligibility Test (CTET) Paper-II, conducted by CBSE in accordance with the Guidelines framed by the NCTE for this purpose. The candidate also should be proficient in teaching in Hindi and/or English Medium.

You have shown your inclination for doing two courses at the same time and I must applaud you for that though it is a tough option but if one can give time and do efforts it is worth exploring. Only problem is that the present UGC rules do not allow us to go for two regular courses simultaneously and you might have to choose one of them in regular mode and other in correspondence mode.

There are two tests in CTET exam - CTET Paper-1 (for class I to V teaching) and CTET Paper-2 (for class VI to VIII teaching).
For the first one (CTET paper-1) the following candidates are eligible -
(a ) Those who have passed the Class 12 exam with a minimum of 50% (45% for reserved categories) of marks and have also passed the D.Ed (Diploma in Elementary Education) course.
or
(b) Those who have passed Class 12 with a minimum of 45% of marks and have passed B.EI.Ed course (Bachelors in Elementary Education).
or
(c) Those who have passed Class 12 with a minimum of 50% of marks and have completed D.Ed in Special Education.
or
(d) Those who have passed Bachelor's degree and B.Ed with a minimum of 50% of marks.

For the second one (CTET Paper-2) the following candidates are eligible -
(a ) Those who have passed Bachelor's degree with a minimum of 50% (45% for reserved category) of marks and have also passed B.Ed.
or
(b) Those who have passed Class 12 and B.EI.Ed with a minimum of 50% (45% for reserved category) of marks.
or
(c) Those who have passed Class 12 and have passed B.A. B.Ed/ B.Sc B.Ed integrated course.

As mentioned above, you have done BE in civil and pursuing B.ED. So, you are eligible for the teaching field. After completion of a B.Ed, you can apply for a teaching job. From time to time, applications are invited for teachers recruitment on the state level for which written test followed by interview are conducted. You will have to qualify for this test for being a teacher.
As per govt rule, for the PGT position candidate should have a master's degree(any discipline) with a minimum of 50% marks from a recognised university. B.Ed is also a compulsory requirement for this position. So, If you complete M.A in economics with 50% marks and B.Ed also then you would be eligible for the PGT position.
In the case of TGT, the candidate should have a graduation degree with a minimum of 50% marks from a recognised university in the concerned subject. They should also have a B.ED degree from a recognised university for this position. CTET is also an essential requirement for being a teacher in govt sector.
Your other query is about getting two degrees simultaneously. As per UGC guideline, It is not allowed to take two degrees simultaneously. If you want to pursue two degrees simultaneously then you will have to choose one in regular mode and another in distant mode.