How do i add a model to a function?

I'm trying to make a double jump function that shows a model/effect i made when you jump/activate the function almost like a projectile, im super new to lua and am a bit confused on how this can be done. picture of what i'm trying to do for reference. Thank you!

https://gyazo.com/c81828096bceac1659c0b1625e0da5f1

Correct me if I'm wrong, the humanoid has an event called: Humanoid.Jumping What you can do is listen for that event

Humanoid.Jumping:Connect(function(isActive)
	if isActive then
		-- Do desired task
	end
end)

You can read more about humanoid action events here:

Humanoid Action Events

If this helps I would appreciate an upvote or solve. Good luck!

Best Regards, -Syn

As syn said above the humanoid action events place is a good place to look for extra info on listening for said events. Good luck!