Keynote isn't crashing on my MacBook Pro. Is it possible you're running low on storage space? At System Settings>General> Storage, my Mac says 745 GB of 1TBB used. What does yours say?
Try these things:
- Restart the computer (of course)
- Re-start in Safe Mode. This bypasses certain potentially disruptive processes, and it often helps. Safe Mode is different for different computers, so see this:
Start up your Mac in safe mode - Apple Support
- Make a new keynote file to work with to see if it was the file itself that was corrupted.
Make a new user and see if the same problem recurs with it.
The idea is to find out if the problem is with the file, with your account, or with caches and login items, and stuff like that. One of these steps may fix the problem, but their failure to work also helps figure out what's happening.
Let us know what happens…