Hello Rahul

There is no such option. I mean how you can do a technical course online. There are various different other course you can do while doing btech but not btech. 

I mean how you will perform the lab work, how will you perform your practicals. Please think.

Dear aspirant, you have to take admission in a college to get the degree but if you just want to gain the knowledge then you can do it by checking the syllabus and reading the books or by browsing the youtube, you can get every kind of knowledge on your own but for the degree you have to join a college. 

All the best:)