I was taking down a light fixture in bathroon. The black wire touched the metal braket for the light and both overhead vanity lights go dark. I checked the breaker but none were tripped. Still no power, checked all GFI plugs surrounding the vanity and thy all have power. I checked the switch and it appears fine. What next?

. I checked the breaker but none were tripped
I assume that means you just looked at them. Not all breakers move to the off position when tripped. Some only move a little. You can tell a tripped breaker by pushing toward the on position. If tripped it will feel spongy. Reset by turning off and back on.

The other way it may have happened is if the power was back stabbed from an outlet and the surge burned the back of the outlet. Check the wiring path. Otherwise, there is a tripped breaker.

Have you replaced the bulbs on the vanity since the arc?