if you're looking to improve basic stuff quickly there are custom maps to help learn and improve your builds/edits, raysfire actually put together a pretty good edit practice map if you wanna check it out
https://www.epicgames.com/fn/5808-8125-5957
https://www.youtube.com/watch?v=rePKEat3HNU
outside of that learning a few drops really well and knowing the possible chest spawns in said spot and practicing rotations from those set drops helps a ton with making it consistently into late game. Probably goes without saying but landmarks without names are ideal since the named drops are all usually pretty popular
the fortnite demo system is actually really comprehensive so you can also use that to go back into comp games and try and demo review certain fights you're taking based on loadout and playstyle