my 1yo boy wouldn't let me brush his teeth and wouldn't take his medication..help!

Hi, I suggest whenever you make him brush, you too brush with him. When he will see you brushing, he will do it without any fuss. Kids like imitating. Also, you can play some music and then in a sing song way make him do brush. Whatever you want to make him do, do not take it as a task. Always do it in a playful way so that he doesn't even come to know that you made him do anything.

My 8 month old is snatching the toothbrush from us when we tried brushing, so what we do is we hold his hand to teach him how to brush one round n 2nd round I let him brush himself ( more like playing for the 2nd round haha)

Heyy this may help https://sg.theasianparent.com/kids-hate-brushing-teeth