Heyyy dear,

A one- or three-year diploma programme in interior design covers the fundamentals of creating interiors for a variety of locations, including commercial, residential, etc. This course's major goal is to give students a thorough understanding of the fundamental ideas and concepts.

The colleges that do offer are -
JD Institute Of Fashion Technology, Hauz Khas Village, New Delhi
JD Institute of Fashion Technology, Aligarh
IMS- Design & Innovation Academy
Just Designs Institute
Interior Design Courses-IDCDI
Apeejay Institute of Design (AID) New Delhi | Best Fashion, Interior, Graphics Design College
Indian Institute Of Art and Design (IIAD)

To know more -
https://design.careers360.com/colleges/list-of-diploma-in-interior-design-colleges-in-india

Thank you