Dear poker players

I spend 2 days looking for basics theory and basic concepts about MTT on this site, but to be honest with you I couldn't find any. I was thinking if I will start watching videos i will start have question like that.
Why in MTT he Can/t open UTG with ATs ? Why he open 3x no 4x? Why he can't play this same hands all the time during whole tournament (stack size). You know what I mean?

So there is question !

Where I can't find solid information about theory and basics concepts. I mean really solid that after that i can't start open my mind for new things like starting opening my range. Trying re-steal depending on tells. etc.

Dear players what you will suggest to beat first and have solid fundaments. I mean time flowing and of course some of the information are outdated.

If there is none i will say "Modern MTT Bible" so just tell me which direction should i follow and whats the right path is it.

I believe you were in this same stage like me :)

P.S. sorry for my English. Try my best. Waiting for any replay. :)

Knights regards
Anzaker