How do I get a summer internship in IISc Bangalore?

The only way to get a summer internship at IISc is through IAS (Indian Academy of Science). And you need to be in at least 2nd year to apply for it. Once you have applied, your application goes through professors whose departments are in need of interns.

Inters usually receive a stipend in return for their contributions. The professors expect you to be skillful and make big contributions. You can gain some prior knowledge related to the project before going for it. These internships are not for short time periods as the minimum time period for an internship is around 6 months.