Hello dear,Most people doing internship at BHEL enter through references given by existing BHEL employees. So, that is the easiest way to get an internship.

From what I have gathered you need to get a letter of approval from the Training & Placement (T&P) department of your college or institute. The letter should be addressed to -
The General Manager, Human Resource Development Centre BHEL.

Attaching here the BHEL application form I got from their official website -