you don't need to watch videos of the game though. ive avoided those videos and i beat mom's heart/it lives constantly in the original and i beat mom in rebirth after my 3rd try
you just gotta play a lot, that's all
still, those videos taught me a lot of useful strategies, all i needed the gameplay for after that point was to just get a feel for the controls and then i was good to go.
its probably a lot better to just play and get better through that though.
also i beat shoel before i even "beat" moms heart, get on my level.