extend time that apps keep running on Catalina 10.

By logging you out, do you mean that the Mac screen saver kicks in after 10 minutes, and you have to sign back into your Mac through the screen saver login panel? If this is the case, you can do two things:

1. System Preferences : Security & Privacy : General panel
   1. Deselect Require password [ immediately ] after sleep or screen saver
2. System Preferences : Energy Saver panel
   1. Increase your Turn display off after setting
   2. Optional for Power Adapter : Prevent computer from sleeping automatically when display is off

Please navigate to the Mac App Store and download the free version of EtreCheck OR please click www.EtreCheck.com where you will find the app. Once you downloaded the free app and created the report please post it as your reply to this message. In order to post it, please use the following link for more detailed instructions on how to correctly include the results: 

https://discussions.apple.com/docs/DOC-250000211

We can then look for obvious issues that may be causing your problem.