Can I do M.Arch after BTech Electronics and Communication engineering

Architecture is a professional degree and for doing M.Arch. you are supposed to complete B.Arch. first.

B.Arch. and then M.Arch. - that is the way to become a licensed architect.

Anyway there is always a round about way of doing things. After completing your B.Tech. in Electronics you can try to get admission in M.Tech. in Civil Engineering and enter the field of Architecture without a valid license. After you get some experience you can manage the show. Another way is to do a diploma or certificate in Architecture and start your own work or join a company and work under some qualified Architect.

In India the minimum eligibility criteria for joining M. Arch is a bachelor's degree in the same subject with minimum 50% marks. But you have a different qualification. Hence you may not be able to join in M Arch in India directly. You can try doing M.Plan (Master of Planning for which any BE/B Tech is eligible and almost similar to B.Arch. You can give a thought about that.
The Harvard University, USA is offering M.Arch. The eligibility criteria are as follows.
The program leading to the Master in Architecture (MArch) is an accredited professional degree intended for individuals who have completed the bachelor's degree.
Individuals who have completed a four-year Bachelor of Arts or Bachelor of Science degree or equivalent in any field (architecture or other) are eligible for admission. Preference for admission is given to applicants who have completed a balanced undergraduate education that includes study in the arts, sciences, and humanities. Similarly, many foreign universities are offering this course. You can go through the university web page to get all the details and take a decision.

No, there is no doubt about it. No Indian University would allow you to take admission in M.Arch. after doing B.Tech in Electronics & Communication Engineering.

As far as my knowledge goes, no reputed University in any country allows such admission in M.Arch.

No, you cannot do M.Arch after completing your engineering graduation in electronics and telecommunication. However few of the universities offer to have admission in post graduation course of architecture if you are civil engineering and have scored well in your engineering courses like school of planning and architecture (SPA) in Delhi.

Still, you need to inquire about the same from the websites of the colleges who offer M.Arch.

I think that you are supposed to complete B.Arch. first.