It will not hurt a thing to drive your truck without a bumper...until you hit something.

Most bumper dents can be fixed with a block of wood and a swinging press (sledge hammer).

Take yours off and try to straighten it. While it is off you might as well repaint it unless it is chrome. Be sure to use the wood block and do not hit the hammer directly on the metal.

Once you have the money available or when one falls in your lap, you can replace it with a new one.