I just took dwn a ceiling fan in the den to replace with a light fixture.The wires in the ceiling are red , black, white and a ground. The wires from the light fixture are black white and a ground.I have a dimmer switch on the wall and now I can only turn the light on with the dimmer switch. What do I do with the red wire?

Thanks in advance.

Presumably you have two switches on the wall. One for the fan of the fan/light you removed and one for the light of the fan/light. Apparently the red was connected to the switch for the fan and the black was connected to the dimmer for the light.

If you like what you have, just cap the red wire with a wire nut. If you wish you can move the new light operation to the regular switch by connecting the black to the red and capping the black.

Thank you.I think I will switch them so that I can use the switch to turn on the light versus just the dimmer