It is a broad question, and the answer will depend on how well one can opt for premium clients. For example, if you have a couple of years of experience dealing with corporate clients to design offices, the pay will be much higher than one doing shop designs.
However, an experienced interior designer earns INR 10 to 15 lakh annually. Further, if you ask me about the salary, it might be 5 to 6 Lakhs for a couple of years of interior design experience.