I regret you are not eligible for M.Tech, for pursuing M.Tech. following is the eligibility criteria for pursuing M.Tech through GATE

•    A 4 year Bachelors degree in Engineering/Technology/Architecture/Pharmacy after 10+2; those in final or pre-final year can also apply.
•    Masters degree in Science/Mathematics/Statistics/Computer Applications or equivalent; those in final or pre-final year can also apply.
•    Aspirants in IInd or higher year of 4 year Integrated Master’s degree programme (Post-B.Sc) in Engineering/Technology Or IIIrd or higher year of 5 year Integrated Masters degree programme and Dual Degree Programme in Engineering/Technology.
•    Aspirants having qualified through examination conducted by professional societies which may be recognized to UPSC/AICTE or equivalent.

So, i will suggest u to go for Masters in computer application or mathematics or science or stats...and then u will be eligible to appear in GATE.