Where can I study UE4?

Yes, this is the question: where can I take a professional course of UE4? I can’t found one.
Thanks.

Take a look at the Udemy courses : Unreal Engine 4 Course (Create Multiplayer Games with C++) | Udemy and Super Simple Online Game Development: Unreal Engine and C++ | Udemy

The tutors for these two are professional instructors and it es said, that this are the best courses online.
I have heard many good things about them and already bought the first one, but still need to amount some time myself for it.

When you are new to Udemy, then please take note about the prices, that there are constantly sales.
So simply wait a few days till the course you want is 80% to 90% off or in the range between 20 to 10 bucks.

​​​​​​​I bought already many courses for different topics on that site and many others will recommend them too.
Currently I’m learning digital drawing and concept design there and it is awesome!

So I wish you good progress and of course fun!!