We replaced a fan that required the three wires, white, black and red with one that is controlled by a remote and only uses the white and black wires. My question…since there’s a light switch that used to control the light can I use the red wire and switch to control 4 can (pot) LED lights? Thanks for the information.
You'll run a /2 cable to the fan-box from the can-lights and connect bare to the rest of the bares, white to the rest of the whites, and black on the new cable to the existing red wire -- wire-nuts or Wagos are available at any big-box or hardware store. Just watch your box fill and make sure you aren't overstuffing the junction box -- you may need a round/octagon volume marked mud ring to add a few extra cubic inches with the additional cable/clamp installed.
And yes, don't put the can lights where the fan blades can block them, otherwise you'll get annoying shadows when both are on.