listudy VS chessmadra-frontend

It comes with experience. There is a website called listudy.org that has a section called “Blind Tactics” that might help with visualization.

Listudy: Memorise openings with spaced repetition. Chess Endgame Training Chessercise: Practice chess with YouTube. Chess Madra: Build and practise an opening repertoire. Aimchess: Learn your strengths and weaknesses.

If you are trying to practice a certain opening, I would highly recommend listudy.org just to build that spaced repetition in your head.

I find https://listudy.org very useful for drilling lines. I don't see it mentioned often, but it allows you to import any lichess study (selfmade or other) into it and it'll pick a random line that's up to you to correctly play out until the end. Works very well if you do it enough

I use private Lichess Studies to store/build my repertoire. Start "choosing" your preferred responses to various opening moves and store them there. Start 1 move deep at a time and branch out slowly. At low level of play it's actually better to go just a few moves deep and have some canned responses to common bad moves from your opponents. You can import your lichess study into listudy.org which turns your saved opening prep into spaced repetition exercises to practice.

listudy.org

Second, you can check out https://listudy.org which can do this with lichess studies.

Create a repertoire with ChessMadra

Listudy: Memorise openings with spaced repetition. Chess Endgame Training Chessercise: Practice chess with YouTube. Chess Madra: Build and practise an opening repertoire. Aimchess: Learn your strengths and weaknesses.

Chess Madra for building and practicing an opening repertoire.

Also there is always Chessmadra where you can build an opening repertoire tailored to the moves you encounter at your rating.

Check out ChessMadra. It's more of an opening repertoire builder than "randomly selected", but with spaced repetition.

It doesn't make much sense to study openings to an absurd depth, as you said. Opening principles are much more important as soon as you are taken out of book. But It should be possible to build your repertoire with the Catalan in mind for your rating range with ChessMadra. Put in your rating range, build and drill it.

I use chessmadra.com. Works pretty well for building a repertoire and practicing, plus had access to lichees opening database. Is completely free.