Multiple abilities for sword

Kay, I’ve seen atleast like 5 different posts like mine, however… I’m not the sharpest tool in the shed, and I take a minute to understand things, I’ve been working on a mod for silly’s for about 4 days now. I have a sword base, 2 abilities and that’s about it, I’m trying to figure out how to, with a keybind let’s say “r” you can swap between abilities say example 

Fire ball, anddddd black hole. I can swap three them, if anyone can help me please I’d appreciate that.