Do you also get a notification that all of your scratch disks are full? It's bad when you don't know much about technical issues. But it's good that the Internet exists nowadays, which can help you get out of almost any situation. I found detailed instructions at
https://macflypro.com/blog/scratch-disk-full-mac.html . Your photoshop should have a built-in tool for clearing cache and removing unnecessary files. In general, if you do everything as written, then quickly fix this problem.
