Sillman has written a ton on analysis issues of all sorts. I believe that you can look through *all* his past articles on chess.com (there are a lot) many of which are on or related to how to analyze, though fewer with a tactical focus.
I'm not sure how much it will help with the specific situation at move 20 (though it can't hurt), you mostly just got a bit lost in the complications. It does look like you didn't maintain steady analysis EVERY move, since your 21st and 22nd moves were outright blunders. So if you didn't see through the thicket on 20, okay, but the situations at 21 and 22 were simpler, and I am confident that you could have made much better moves if you had done your thorough analysis process from scratch at those moves. I think maybe what happened is that you thought you worked through things at 20, and didn't re-analyze once things went differently?
Here is a game I just played and I think I played it pretty good until one point when I went down two pawns at the end for no real compensation. There was one critical point that I saw, and I realized my mistakes after going over the game again. Everything seemed okay when I was playing it in my head but after the combination I was just down two pawns.
I will add what move I saw in hindsight, but I was curious how I can better analyze these types of positons in the future.
Hard crunching move by move analysis eats up a lot of time and mental resources with positions like the one I got too, and I don't have enough experience to recognize advanced patterns to simplify it into more reasonable chunks.
I practice a lot of tactics on here and it helps to some degree, but I am just curious what techniques higher rated players use to help simplify things. I know about starting with looking for "power moves" like checks and forks and skewers and stuff, but when your trying to calculate 5 moves in and keep the board in your head it starts to get fuzzy for me.
I can do about 3 moves and see everything clearly but after that it gets a lot harder.