scanning a score into musescore

You can try the experimental online service in File / Import PDf, or any of the commercial programs designed to do this. Then expect to spend time fixing the errors, since this kind of AI technology is still pretty new. With luck, it might be faster than just entering the music yourself normally, but don't count on it.

You'll soon recognize which scores scan well and which scores won't. You'll get better at editing the mistakes it makes. I've recently been scanning scores instead of entering them by hand. Some scores work better than others.