This Unreal Engine 5.3 Gameplay Ability System video is about using Blueprint Function Libraries in both C++ and Blueprints.
We start by creating the C++ Blueprint Function Library and adding a simple function, and then we create the Blueprint version of a Blueprint Function Library with another simple function we might want to re-use many times. Next, we show how to call the Blueprint BFL and the C++ BFL.
https://dev.epicgames.com/community/learning/tutorials/r657/unreal-engine-50-blueprint-function-libraries-in-c-and-blueprints-let-s-make-a-top-down-shooter