How do I know what to put in a function Argument????

A normal function like this

function example() ... end

you can also write it like but u still have to name your function

example = function() ... end

what goes in are variables that can only work in the function

function example(a,b,c) print(a,b,c) end

example(1,"hello",true) -- call function

and other functions like wait() which you have to put number in how long to wait

you write the function in roblox wiki or search for some and it tells you