Hello Everyone,
My name is Mohammad Al-Shareef, I am 21. I study computer science.
I have been playing the Piano since I was a kid. All of these years without any guidance. I feel like they were almost useless years in terms of learning Piano. I just hear some pieces that I like then I try to play it on the "Piano" and I used Synthesiea. We had a very old keyboard and that was my instrument. My music theory knowledge is limited it's from random videos on Youtube and Fundamentals Of Music Theory course on Coursera.
Recently (5 months ago), I decided I want to get into Piano seriously. I bought 88-key digital Piano. I "learned" how to read sheet music (I put learned in quotes because I am still a beginner and hearing the piece helps me so much). I learned to play these pieces (all from sheet music).
1- Chopin nocturne No.2 (it took me a month)
2- Chopin Prelude in E minor (It took me 3 weeks)
3- Erik Satie - Gymnopédie No.1 (it took me a month, the first piece using sheet music)
4- Chopin - Nocturne in C Sharp Minor (No. 20) (still in progress)
5- Other pieces like (River flow in you, happy farmer by Schumann, Moonlight Sonata 1st mv. but not all of it) I learned these with Synthesiea before I learned sheet music.
Before learning any piece I search for it's difficulty. I have been looking for what to learn next. I really want to play Liszt Liebestraum no 3. I desperately want to play this piece. But from what I have seen it's very difficult (at least to me).
What's also disappointing to me that while I am reading on the internet I read concepts like wrist technique, finger dexterity ... and so on. I don't know them. I never paid any attention on how my wrist is on the Piano. I don't know what should I do to improve things like that too

And how my practice routine should be
What I want is something like a road map or some guidance on what should I do to play hard pieces like this one ?One last thing, I read lot's of people on the internet saying I should get a piano teacher. I really can't get one. Does that mean I can't learn playing hard pieces ?
Thanks in advance.