Crashing

Is PPro Crashing or is it hanging.  
Do you get a crash dialog that comes up asking you to send crash details to Adobe?  
Please make sure you fill that out and send it in. 
Please add comments decribing what you were doing before the app crashes.  Example:  Just launched the app and it crashed.  OR,  I was exporting my project and it crashed.  OR  I was just doing some editing and when I added an audio track, it just crashed.    You see, you don't have to provide very detailed info. Just basic info will help.  

What are the complete computer specs, including hard drives (how many, what kind, what is on each, what capacity, and how full)?

Delete the Media Cache and Media Cache files:
https://community.adobe.com/t5/premiere-pro/faq-how-to-clear-your-media-cache-in-30-seconds-in-premiere-pro-2020/m-p/11017257/thread-id/260446?page=1

If that doesn't work, try resetting the preferences:
https://community.adobe.com/t5/premiere-pro/faq-how-to-reset-trash-preferences-in-premiere-pro/td-p/8236158?page=1

If that doesn't work, try resetting the Workspaces:
Reset a workspace
Reset the current workspace to return to its original, saved layout of panels.
1. Do one of the following:
• Click the Workspace menu icon and select Reset to Saved Layout.
• Choose Window > Workspace > Reset to Saved Layout.
from here:
https://helpx.adobe.com/premiere-pro/using/workspaces.html

If that doesn't work, try Preferences > Audio Hardware and set Input to None.

If that doesn’t work, try updating or rolling back your graphics driver directly from the video card manufacturer’s site. If NVIDIA, do a clean installation of the latest Studio Driver (NOT the Game Driver)

If that doesn't work, try creating a new project and import the old one into it.

Also, please help us help you:
https://community.adobe.com/t5/premiere-pro/faq-what-information-should-i-provide-when-asking-a-question-on-this-forum/td-p/3929027?page=1