Ark: Survival Evolved doesn't have a native option to control the hotbar (1-0 Keys) using the scroll wheel. ArkScrollHotbar adds this function to the game. This works for any game, but shouldn't be required in most properly programmed games.
The program works with a single python script (main.py) which "translates" mouse scrolling actions into the corresponding key input used for the hotbar. In the Game, you need the hotbar slots bound to 1-0 number keys (like default) and have nothing bound to scroll up/down.
You start the app by double-clicking the "ArkScrollHotbar v1.0.bat" file. Once it says "RUNNING", it's running.