Hello Gautam, 

According to eligibility criteria of GATE exam one must pursue 4 years 10+2 Bachelors degree in engineering B. E. /B. Tech or 3 years after B. Sc/Diploma in engineering/ technology or those who are in final year of the program. If you are in the final year or have completed your course then you could apply for the GATE exam.

Yes of course you can apply. Those of bachelor's degree holders in engineering or technology (4 years after 10+2 or 3 years after b sc or diploma in engineering or technology) and those who are in the final year of such programs can apply for gate.