I've no problem with using LibreOffice for most of my document needs, but i haven't found a good substitute for microsoft's OneNote yet. I mainly use it to plan my RPG games and it helps a lot. What alternatives are there for organizing notes on linux, with similar features to those that OneNote provides?
Obsidian could work, its a markdown editor but I doesn't have any handwriting or drawing support, also its sync feature costs money but you can use nextcloud or github to sync your stuff anyway. An opensource alternative would be logseq but I prefer Obsidian