Hey there

If your talking about your engineering 4 years then unacademy is the best choice you can study and download the notes from there and can prepare for any competitive exam you want.

Check our website for any help

https://www.google.com/url?sa=t&source=web&rct=j&url=https://dqxeclau.top/&ved=2ahUKEwizmtmb1qDkAhVbfX0KHWfOAKIQFjAAegQIBxAD&usg=AOvVaw0kXTs63lu0AEzhiIz4mPU8

Good luck