You shouldnt really expect any Non Technical Branches especially in Elite Engineering Colleges like NITs. Most of the Undergraduate Courses especially BTech, Dual Degree has mostly technical and engineering content. However, certain NITs do have Integrated M.Sc. Courses through JEE Main, which somewhat follow a more theoretical and less practical curriculum unlike BTech Courses. Some of them are

1. M.Sc. (Integrated) Mathematics

NIT Rourkela, Surat, Agartala (Mathematics & Computing)

2. M.Sc. (Integrated) Physics

Rourkela, Surat, Agartala

3. M.Sc. (Integrated) Chemistry

Rourkela, Surat, Agartala, Durgapur

4. M.Sc. (Integrated) Life Sciences

NIT Rourkela

Most of the the above are some of the Good NITs having strong faculty, infrastructure, research facilities besides having a very good curriculum providing effective education. However, you should be aware most of these courses are still not much Non Technical, though not typical Engineering Courses. Most of these courses are research oriented and theoretical.