Please advise and don’t mom shame me

First time mum here and in serious need of advice. My 2 year old often gets tongue oral thrush and part of me feel that this is caused by lack of proper oral hygiene. Now the problem is that my child refuses to brush his teeth.. the only way to brush is teeth is if I pin him down but I feel like maybe that’s too much force for a child? Even when pinned down, he closes his mouth and you can’t get through… he will bite the brush instead. I have tried everything such as spending so much money on toothbrush that sings, buying one that has that app thing, getting him to brush when we are brushing… nothing seems to be working. I don’t know what else to do. Any advice would be very much appreciated 😭