Adobe is good but the monthly subscription price costs a lot.
I’m looking for a cheap PDF editor with basic features like editing, scanning, and annotating
Are you satisfied with the performance of the particular editor you are using? Can you share your experiences in this regard?
OOC, as a non tech user, does OpenNotes not become a bit tough for generic user? I use NoteBloc, though not opensource (afaik), but I any ways deny network access to it.
If you want peace and productivity with all modern features do use Microsoft 365 (formerly Office) android app. Use in-built lens option to capture and make pdf or just use its pdf tools.