My browser / operating system: Windows NT 10.0, Chrome 120.0.0.0, Flash 32.0 (release 0)
when i was playing scratch story mode and i got to the final part the screen was like a file with a face like this : x_x and it was in the top left of the project screen
and i lost my progress

Did the page say “Aw, Snap!”? if so, that's a problem with chrome, not scratch. it's possible that you just ran out of memory by having to many tabs open.

no it just sayed the project name

Try clearing your cache, taking a screenshot of it, and then uploading it onto a whitelisted image host, such as cubeupload. By the way, after you cleared your cache, you could try restarting you PC.

got fixed without doing anything