I have minimal knowledge of music theory and don't have any guidance from a teacher.
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I was wondering what pieces you guys could recommend that will help me improve my technical skill to the point where I can play pieces like:
Liebstraum No. 3/La Campanella - Liszt
Fantasie Impromptu - Chopin
If you are going to do it without guidance, then I guess to play advanced pieces from certain composers the logical way is to work on their output gradually from easier pieces to harder ones and adding some technical exercises or "fingery" pieces (like Bach inventions) to gain more facility. When you have played some composer's music enough, you will start finding it more and more familiar, thus making learning a easier.
But there's no guarantee that you ever will be able to play those pieces to any reasonable standard without some help. There seems to be a certain level of piano playing that one can reach by pure determination, but after that things get so much harder that without proper technical foundation and guidance no amount of practice will get you there. If one could just learn to play advanced piano music instinctively with hard work, we would have a lot more self taught amateurs that are not a pain to listen to

So I would recommend to get some proper guidance on how to tackle technical and musical challenges of advanced pieces and what and how to practice to gain all the physical skills needed (tailored to your specific needs).