Replacing ceiling fan/light combo with LED light only
The black/red/white at the ceiling junction box are travelers.
Most-common wiring will have the following:

You're going to find power at the existing switches, one switch should have two black and one switch should have one black and one red. One of these switches will be downstream from the other.

Figure out which is downstream and delete it (switch, wiring, and the box if it's a separate box demo the box or use a blank plate or if it's the same box go buy a blank insert if you have decorator switches). Most common wiring practice will have a cable entering one of the switch boxes, three-way nutted to another cable leaving the box and a pigtail to the switch in that box; if you have that, you'll pull them apart and test them all to see which is carrying the power.