Potty training- toddler doesn't like underwear

A❤️C

I want to potty train my toddler. I've tried a couple of times in general (he shows all the signs and is about 2 1/2 now) but if I put on underwear he screams. I tried no underwear and he screams. He's used to the feel of a diaper I get that. Should I just throw all the diapers away (at least make him think they are all thrown away?) or what should I do? I don't want to traumatize him but I'm kinda at a loss. Could he just not be ready?