Thanks! I tried to look for this issue but I could not find it here!
To save your files on iPad you have to be running iOS 10 or later. First go to the files app click on On My iPad, click the Minecraft folder, games, com.mojang, find the one that says mincraftworlds and hold on it till the menu pops up, duplicate it, and move it to a different location. When you reinstall the app move the folder to that location deleting the other folder with the same name.
I have the same issue with the new Magic Keyboard on IPadOS 18 Developer Beta 2. So I doubt it is an Apple issue.