GATE

You follow the study material of Made Easy coaching centre in self and take the test series of made easy every year. Follow the previous 10 year papers.

There is a lot of difference between JEE and GATE. JEE is an exam conducted to get entrance to any engineering college whereas GATE is an exam conducted for entrance in PSU, or for M.Tech.

Yes, you can as if you are an electrical or mechanical engineer then you get a chance to get job in the Indian railways, but you have to score good marks in the GATE exam.

Hello Karan,
Yes, droppers are also eligible for GATE exam as this exam is both for job and for higher studies, so you have to score good to get selected.
All the best.

No, you are not eligible for GATE with B.Sc in electronics (3 years). If your B.Sc is of 4 year duration then you are eligible otherwise after M.Sc you are eligible. Visit the link: http://www.gate.iitr.ernet.in/?page_id=266

JEE Mains is just a beginning. GATE is the advanced version of JEE Mains but it is a bit easier than JEE Mains.

Hello Yawar,
You may refer to the links below for the list of colleges that accept GATE exam scores:
1) https://www.shiksha.com/articles/institutes-accepting-gate-scores-for-me-mtech-phd-admissions-south-india-blogId-6655
2) https://www.shiksha.com/b-tech/articles/colleges-accepting-gate-scores-for-me-mtech-phd-admissions-north-india-blogId-6654