Dear student.

Greetings.

You have not stated your question correctly. If you are talking about the best engineering branch, then CS branch has the highest scope nowadays. Kindly mention your question clearly so that we can provide you proper explanation.

Thank you.

If you are asking about learning various courses of Engineering the I would Suggest Coursera Basically for CSE and IT Engineering they offer certification courses which can help you in grabbing Job.

If you are concerned about core Engineering then NPTEL is a good platform where you can find almost all the courses of Engineering, But old videos are poor in Quality so you can take help of MIT videos on Youtube. 

There are a lot of good channels which offers great Engineering content for free, and if you need any sort of career advice then Careers360 is the best Platform.