How to unlink my MacBook Air and iPhone with same Apple ID

Hello everyone. I have been an IPhone user for quite some time but I have been using windows laptop but recently I bought a MacBook Air (M2). I signed into the MacBook Air with my apple id and when I created folders for my school work, they appear in my iPhone also. I don’t want them to be in my iPhone. What should I do to unlink both of my devices? And if I unlink them can I still use my MacBook Air? Because I only have 1 apple id. Thank you.

[Re-Titled by Moderator]