I can recommend Zim wiki which is a GTK+ desktop app that works as a personal wiki / notebook. Has a WYSIWYG editor and can export to different formats, it can even render the wiki as html and serve it. Also supports plugins for extra things like tables and charts if you wish.
You can have separate notebooks for each project like home/work/etc. You can commit to git from the UI, have git hooks set to automatically push to a remote on every commit.
Not fancy but very functional and pleasant to use.
https://zim-wiki.org/