I believe my power source is in the ceiling. I just want to wire a light but use a leviton switch and dimmer at the wall. Can't figure this one out. Can you help. There are two red wires, one black and a ground. What's up with the two reds?

Question needs more details. Let me answer as if you have one light and one switch, and one cable coming into switch box from ceiling.

Usually a switch-dimmer combo operates 2 different Loads (lights).
One light is controlled by switch, other by dimmer.

If power source is in ceiling, then one cable enters switch box.
Cable has black, white and ground wires
Old switch had 2 brass screws where black and white wires connect
Black wire brings Hot down from ceiling, and white wire connects back to Load (fan).
Neutral wires are in ceiling box, and not inside switch box, and are discussed.

With new dimmer: Black Hot wire from ceiling connects to dimmer black wire.
White Load wire connects to one of the red wires.
The other red wire goes to another Load, which is unknown at this point.

Add a comment for more free help. Say what cables and wires enter box, and what Loads you are controlling. Also add exact model number so expert can reference manual. Levition instruction sheets and manuals usually have toll free number.

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