Minimize and close out buttons disappear in full screen mode in apple macbook air M4

you can see in this photo that the minimize and close buttons are available but then if you see in the next screenshot they are not there and I don't know what the issue is. I have never faced it before in my macbook air which was an Intel 5th gen processor but I don't know the issue with this macbook. If you look there I don't have an option to close my tab which is annoying. It is not an issue with just microsoft one note but also with apps like apple notes. microsoft word, safari. I need help to fix this issue. I also have one more issue which is with this photo. I don't even know why that is there on my homescreen. My microsoft one note is in full screen then why is that there on my screen. PLEASE HELP

[Edited by Moderator]