Form fill up of backlog even sem

The question is not clear actually. You have any problem in filling the application for backlog examination or you have a doubt regarding attending the examination to complete the backlog.
When we write the sem end examinations, if you have not secured minimum marks for passing the examination, you will be failed in those subjects. Once the results are declared and you know which subject backlogs are there. Then you can for the examination along with the next semester examinations.
You can apply for the next semester examination and you can apply for backlogs also. It is always better to complete all the subjects before you complete your degree. Then only you will be given class and people will consider you for postings. You should keep in mind that you should complete before your final year is completed.

You have not asked the question very clearly but what I infer from your one liner crisp question is that you are concerned for clearing your backlogs. You must be appearing in the semester examinations after the end of each semester and if you fail in some of them then they would become arrears for you as backlog and then you are supposed to clear them in the next successive semesters. If you are not able to do that then the colleges give some special relaxations up to 2 years after completion of the main period during which you have to clear all the arrears and then only you would get a certificate of successful completion of the degree from the college or the university. Whenever you appear in the semester examination you would be asked to give a list of all those arrears which you want to undertake along with the other usual papers due in the present examination. Once you indicate that then they would ask you to attend question papers pertaining to those arrears also along with the usual ones of that particular semester. You might be asked to indicate this either online or some physical form whatever be the practice in your college. So, you have to fill the requisite form accordingly. The important thing is that if you accumulate more arrears then you would be loaded more as you will have to clear so many papers at one go. Anyway, if you are unable to do that then they would be carried forward as arrears to the next semesters.

It is advisable that a student should try to avoid these arrears as they affect the study performance in long run as they accumulate more and more to the end of the course and then it becomes a herculean task to cope up in clearing them. Frankly speaking one should work hard and see that no arrear is accumulated for clearing to be done in the later period.

As per your indication, you do have certain backlog papers in your even semester.
Irrispective of even or odd semester, you need to clear all backlogs within the time prescribed by your university and failing to clear the backlogs would affect your final examination. Even if you have cleared the final examination, you would not get your final degree.
While attempting your current semester, you will have to work out a planning to clear your backlog papers even with the proper indication in the examination - form.
Ensure that your backlog papers are cleared along with the papers of current semester.
Delaying your backlogs further would be a cause of worry for you and would create pressure in the line of preparation for the examination.
Hence be serious in your attempts of backlogs, in case you face difficulty in the preparation, meet your professors of the concerned subjects so as to have a better guidelines for such papers. You may also look into the past question question papers of the university in which you have backlogs. Going through the past question papers, you could infer the pattern of questions likely to be asked in the next time.

Can I appear in this even sem or not?

You have passed out but not completed your all the papers it means that your degree is still blocked. If it is so then as per the UGC guidelines you are supposed to clear it within 2 years of your scheduled final year which was 2019. So, you can apply to appear in those left out or arrear papers and they would accommodate you in the coming semesters and as you have time up to 2021 , you can comfortably do it and hopefully clear it by that time and finally get your degree. You will have to deposit the necessary fee for examination and apply in the prescribed format as issued by your institution. I suggest you to take initiative and go to your institution and find out the modalities in this regard. They would not be informing you that please come and clear your papers. It is unlikely if you get such a call from them.