How To Prevent Mac From Automatically Logging Out

The option is found in the System Preferences window as shown below
– Security & Privacy General and then
– Advanced dialog.

Choose Apple menu
- System Preferences
- Click on Security & Privacy
- Click General and
- Click the on the lock icon 🔒to unlock it
- Enter an administrator name and password
- Click Advanced

Uncheck “Log out after minutes of inactivity as shown below and click Ok

Finally Click on the Lock again, to activate the lock as shown below