Dear Venkat, BSNL has a programme called BSNL Employability Enhancement Training Programme (EETP). This is a joint initiative by AICTE and BSNL. This is apaid programme and is for Summer Internships. You can check these details on their official website. For Internships in BHEL you should be studying either your 4th or 6th semester of Engineering in Electrical/Electronics/IT/Civil/Mechanical/Metallurgical/Computer streams. If you have connections within BHEL, you can ask for reference. If you do not have any, you can contact the HR of the nearest BHEL offices and enquire about possible internship opportunities based on your strean in B.Tech.