I spent AGES trying to do this and trying out all sorts of apps.
The best solution (for me at least) was self-hosting Nextcloud and using its Calendar and Tasks apps (and using it’s CalDAV to keep tasks and appointments in sync in various apps across my devices). I’ve never got the hang of Kanban so can’t comment on how good it is. I also keep my scratchpad/fleeting notes using Nextcloud Notes.
Check out Memos. It does most of what you want. There’s an app, MoeMemos as well. I’ve used Memos as my journal for a couple of years now. (There’s also a sync with Obsidian if you use that.)