I'm a relative beginner, been playing for about 6.5 months now.Out of my other repertoire, I've learned two pieces that could be called "advanced repertoire". But the thing is that it's hard to get them to the quality that I desire. For example, I posted a test run of the Revolutionary Étude, and was lucky enough to receive a scrutinizing comment from somebody to rethink my goals and work harder. So I'm still working on it on and off, and it's getting significantly better, but not good enough for my own judgment or if it were to be graded in an exam. (Please, if you reply, don't ask me to validate what I said. Or to not touch Etudes until I'm 75. I'm going to learn them if it kills me. I'm just asking for help in THIS scenario- well, eventually I'll get to it. Actually, in a couple months or so, for my own amusement, I'll upload what I have just to see the reactions.)
Obviously I cannot go on like this, taking on Etudes and such without a foundation.
To take a step back, should I learn all of Bach's Inventions before recklessly attempting harder pieces? Also, (yes, I know this has been asked since the beginning of time) would Hanon or Czerny be useful and effective?
Thirdly, there has got to be a better way to warm up my fingers than scales. The first few minutes of my piano practice sessions sound like the piano vomiting discordant notes.
If you make an attempt to answer, thanks for putting up with my probably nonsensical questions that I just HAD to ask.