What to do after m-tech for job

Mate, you need to look for the opportunities in your specification. Have you done M.Tech in computers or I.T? If so you will have to search for the software IT industry jobs where M.Tech is required. 

There are some governments jobs for M.Tech done in core areas.

Along with that you can go for PHD or entrepreneurship or teaching jobs apart from just plain private corporate jobs.

Why did you do an MTech in the first place? You would have specialised in some aspect of Civil Engineering with a view to do some further work or take a job that would need that specialty.

Otherwise it would have been to fill time, else to do a PhD and pursue an academic path.

Best to explore avenues in that area.