Keybind doesnt keep abilities unless i continue to hold it down.

Hey, I'm developing an underwater mod that with a key bind will give you water breathing, night vision, etc. and i would like it to work where i click it once and it tuns on, then i click it again and it turns off, but i can only make it work where i hold the key bind down to get said abilities. I don't know how to code so is there a way i can change the procedure to allow that? thank you!