I gave up before trying , my non verbal autistic daughter was too easy . My son gives me anxiety 😭
Your son might confuse underwear for diapers because they both provide a sense of privacy and snugness. Maybe try going commando for a few days? Place him in the potty then step outside for a minute to give him privacy? If you're flexible enough, pee on the potty or have his favorite toy "pee" on the potty Read plenty of books. I went to my local library for this. When we started, I closed off all areas of my house and we only stayed in the living room with the potty seat nearby and when my son began peeing I quickly placed him in the potty and whatever amount was caught in the potty I congratulated him and showed him what he did and say something like "pee came out of your penis and into the toilet. Woah" We then clean up the mess and I would say "no pee does not go on the floor. Your pee goes in the toilet". Once he connected the dots I moved the potty to the bathroom. I really recommend reading Oh Crap Potty Training by Jamie Glowacki. It's super helpful with any dilemmas you'll face.
Maybe it’s too soon for him. My 3 & 4 yr old are trained but haven’t started my 2 yr old yet. I know he isn’t developmentally ready yet. He can’t hold his pee or recognize when he has to go. On top of many other reasons
My daughter is refusing I think she’s just not ready so I stop being consistent. She’s also working with a speech therapist so we’ll start again later in the month or next month.