How to change characterbody2d ID

Godot Version

4.2.2

Question

I have 3 character2d nodes
2 of them cant move (just for testing purposes)
when the moving character collides with either of the other character nodes it returns their ID.

problem is I dont know what their ID is unless I run

var collision = move_and_collide(velocity)
	var collider
	if collision:
		collider = collision.get_collider_id()
	print(collider)

and copy the output from the terminal

I want to atleast be able to find the id without having to run the game but if im able to change the id i would also like to know how

friend told me you cant change ID so imma leave it there