2 toddler questions

When potty training if you say let's go use the potty and they say no or start screaming but you know they need to go and they know how to go in the potty , do you just make them sit even if they cry or do you just leave it and let them wet themselves? I'm having a struggle suddenly with this where he has been doing great and now suddenly he doesn't want to stop playing to use it and will pee himself . If I sit him down he will eventually pee but he cried and screams the whole time but I worry if I just don't make him he will go back to always peeing himself .

I'm also having a struggle with meal times. He will be hungry but he doesn't want to sit he just wants to play so he will scream his head off . My husband always says just let him go and be hungry but I worry that will make him think it's okay to just never sit for a meal .

Help !