Where to see in C++ how implemented blueprint nodes?

I want to know how implemented particular UE4 blueprint nodes.

How to acomplish this?

Right-click on the node, then select “Goto Code Definition” - that will open the header file containing the function declaration in Visual Studio. If you search the header for the function you’ll either find the function itself, or a DisplayName tag telling you what the BP name is an alias for. From there you can open the corresponding .cpp file and look at the code.

go to code definition works perfectly