Can I get direct admission to B.Tech at JIS University, Kolkata?

Direct admission to JIS University in Kolkata's B.Tech programme is not possible. You must pass the 10+2 exam with a minimum combined score in math, physics, and chemistry. The university will then administer the PET entrance exam.
As an alternative, you can take the WBJEE, JEE Main, or CEE AMPAI to

Yes, JIS University follows a merit-based admission process for most of its courses, and direct admission is generally not offered. So if you want to make your career in JIS University, Kolkata then you should clear your cutoff and rules as well as regulation.