There will be 2 kinds of internship

1) u will get paid for internship

2)u have to pay for internship

In 1st category u will be working with the company in real time projects

In 2nd case the training will be given to you by the respected company u have applied and they will guide u to do some projects as a part of ur internship.this experience will helps u to get 1st type internship. With out 2nd type internship also

u can learn through online courses and  youtube

Hey!

An internship is a period of work experience offered by an organization for a limited period of time. Once confined to medical graduates, internship is used for a wide range of placements in businesses, non-profit organizations and government agencies. Students apply for internships during their summer or winter break (UG/PG), interns may be technical/non technical or research or related to you domain. Some colleges offer intern to students or students can apply off campus. It may be non paid or paid(stipend). Internships basically gives you the idea about the ground work or industry. Companies will taught you the work you have to do or if it is a research internship then you have to do a project under the professional mentor.

Thank you