If you actually want to learn maths (that is, if you're not just venting), you could try to ask for help in dedicated math or teaching communities.

The problem with teaching stuff you know, is to put yourself in a position of actually not knowing anything. I'm a software developer and had to teach some apprentices a few years ago, and it was really eye opening to me to see how much assumptions about the apprentice's knowledge I made even though I thought I made my explanation "basic".

It's quite possible that all the tutorials you've read are either for literal children, so they just don't work for your adult brain, or they're intended for adults and assume too much.

On a personal note: how did you get into that situation? Were you home schooled?