You declare variables in the body of the node’s Execute function; (then compile)
The system transforms the declaration into “pins”…
Code away using the variables declared in function body, when the node is executed by the Blueprint the value of variable in function body is whatever value you have wired to the generated pin.
It will take the value of pins in Blueprint node and send to the C++ function written by you, automatically.
I think it’s an interesting way to learn C++, no need to setup class files, modules, project files in visual studio, etc 