EventListeners in functions?

so i would like to instantiate an event listener inside a function, yet am currently unaware of how to begin.

my guess of how to would be like this

function registerPlayer(player)
	--code
	player.Character.Torso.Changed:connect(watchPlayerLocation)
end

function watchPlayerLocation(CFrame)
	--code
end	

is this how i would set it up?

You're correct in theory, but the Changed event does not fire when an object's Position changes.

If you want to have a function update based on Player positions, use the RenderStepped event of the RunService. Use it in a local script.

The connect method returns a value, by the way. This 'ConnectionObject' has a disconnect method (no parameters) that you can use to disconnect the function once it is no longer needed.