

How realistically hard is to build a NoteTaking app like this
I've been searching and testing a lot of note-taking applications for a long time, but I can't adapt to any of them! I find them all very visually cluttered with too many tools, and I simply can't find one that works for me. I've made some drafts of what I have in mind (but I haven't finished yet).
At this point, I'm thinking about studying to learn how to develop them. (I don't have much experience, but I've made basic websites and I like to learn). For people who have more experience, how difficult would it be to develop an application like this one?
Not at the top, not at the bottom, just in a way that allows annotations on the side (either blank or with lines) and the text (PDF) is in the middle?
Another thing I don't like is how EVERYTHING, absolutely EVERYTHING has AI these days. It's impossible to find a note-taking app without AI; I want something simple so I can write with my pen and that's it (I plan to improve it later). Because of this, I wouldn't want to use AI in the process or have that tool.
Please, if pyou know of any, have tips on where to start, or even honest feedback, I'd appreciate it 😭 Thank you.
btw I have a lenovo tablet