Hi FB,
As far as I know, there really aren't any 'corrections' for the 'accidents and deliberate misses' you have asked about. But in regard to the cleanup, be sure not to make it a 'Mommy and Me' time. That is, remove yourself from as much of the cleanup as possible. No friendly chatting, no "it's okay" just "well, you're wet so you'll need to (get cleaned up, change your clothes, whatever needs to be done)" and then leave him to it.
You could try bare bottom, or training pants are great too. I know some people don't always believe this, but the point of not using a pull-up is so that the child A. feels the feeling of wetting themselves, being wet, having wet clothes and B. so that the child IS inconvenienced at times in having to change. After all, the 'reward' intrinsic to listening to one's body's cues and getting to the toilet on time IS staying dry and being *less* inconvenienced by using the bathroom when the body is signalling it needs to go (instead of having to change all of their clothes due to wetting, etc.).
So, keep calm and carry on is about all I can suggest. I have worked with families where a child might use pants-messing as an attention-getting technique, but that's entirely another thing altogether. I do have strategies for addressing this if need be, so PM me if you do. Otherwise, YOUR reactions/responses to his messes will be important. When he wets himself, take him into the bathroom with a plastic bag and let him know that he needs to put his wet clothes in that. Make sure he has wipes to clean himself up that are handy. Try not to do too much for him, other than gentle encouragement, calm emotions during wetting and really, not too much reassurance that "it's okay", because if we act like it's our pleasure to keep changing their wet clothes, they may wet to keep up that connection with us. Instead, this is a time to disconnect and let him work on doing his cleanup, dressing himself. You could even put a towel on a low stool for him to sit on and leave the room, which is what I often did, checking in after a few minutes. (Use a plastic bin or basket for wet clothes if you are worried about asphyxiation due to the plastic bag.) If we act like the child *should be* capable, and that we expect they are capable, they will often rise to the occasion.
And one last thing: never ask "if" they need to go-- they will nearly always say no. Just a five-minute warning and a matter-of-fact "it's time to go use the potty now" is the best way to move things along.
ETA: my son didn't use the potty until 3yr4months. I had time to wait on teaching him... but I understand every family has reasons for starting earlier or later. If your little guy seems resistant, do wait a month and try. My son 'got it' in less than a week because we just gave him a bit more time.