Sorry to heaar about this. This definitely not a typical experience with Illustrator. Let me fix this for you. I would request that if you can share a few more details like:
Operating system you are working on?
Exact version of Illustrator.
When did this start happening? Are there any recent changes made to your system? For example, any antivirus, system updates or web extensions installed recently.
Does it gives any crash report after this? If yes, then please share crash logs by following these steps:https://helpx.adobe.com/in/illustrator/kb/crash-next-steps.html While submitting the crash report please use the same email address, with which you are signed in on this community. This will help us find the crash report and help accordingly.
You may also try giving Full Disk Access to Illustrator in "Security and Privacy" preferences.
Click Apple icon on top left corner of your screen > System Preferences > Security and Privacy > Full Disk Access > Check the box in front of Illustrator.