Heidelberg University (Germany)

For becoming a cardiologist, you necessarily have to do MBBS.

According to my knowledge, pursuing M.Tech in different stream is not preferable. For pursing post graduation there should be sound knowledge on the subjects of that respective branch, which is provided in B.Tech. So, it is not preferable.

Minimum 60 % in graduate is required.

The qualifying marks for general/ EWS category is 90 and 82.5 for OBC/ SC/ ST categories. In CTET 2019 July session, 3.52 Lacs candidates have qualified the exam. Candidates qualifying the exam by scoring the required marks will be issued CTET Eligibility Certificate. This is being shown on internet you can check.

All universities has set a time limit for the students to clear all their backlogs. Check with your university whether your time limit is over or not.

No,
Biology is compulsory for NEET exam.

Yes, you can pursue B. Ed course.

Yes, you can.
For BEd you should complete your Bachelor's degree, then you can do B.Ed.