Thank you, gazumped!
A1 - that's the thing, it's a necessary thing and seems very simple, but for some reason, there is no such function, only a link to child notes, which is not the same at all. The only way out is to make a table of contents and copy it into the search every time you want to find something, but it is not so comfortable. It seems to me that there is some simple solution to this, but I can't figure out how to do it.
A2 - As I understand it, you can do this with a maximum of 100 notes. Do you copy every single note manually once a month or several months? I have about 400 notes 😅. I don't understand why the developers didn't make a simpler data backup system, because it seems like such a great program. Since I haven't used similar programs or real notebooks, this is life-changing for me and I'll always be grateful for it to Evernote 🙏. I've tried Notion, but it's much worse in design for me compared to Evernote, like an old program looks, although maybe it's a matter of habit.