what i have to do after my completion of b.tech? Right now i am in 2nd year

1) apply for jobs in ur field 2) appear for gate for entry into M.tech 3) appear for upsc for civil services

If can affored, then look for M-Tech as it will give you more option to get a decent job. Once u r in job, it is difficult to do further studies. If you are in mechanical trade then you can go for one year graduate marine engineering course as it will give u good salary.