I use Git + Emacs + Org-mode + flyspell-buffer (basically I have a repo that contains all my notes that are mostly written in org-mode or markdown). I don't even use a ton of advanced features that org-mode has (the most advanced thing that I need are tables which are really easy to create in org-mode). If you prefer a video tutorial, you can watch this short series:
https://invidious.weblibre.org/watch?v=vCyBu8Az254&list=PLX2044Ew-UVV0CNIrlst0MkKbu85O7_QT&index=0
Here are some additional hints: https://howardism.org/Technical/Emacs/learning-org-mode.html
If you don't use Emacs, you can use markdown or ascii{doc,doctor}.