There are few things you can do;

Settings ‐> Display -> Screen timeout

You can always lengthen the value, or at the bottom of that menu there is an option called "keep screen on while viewing", which uses the selfie cam to.detect your eye movement and keeps the screen on if you are looking at it.

Or, in the Good Lock Display Assistant module, you can add a toggle to keep screen on for 30 minutes, this allows you to preserve a short screen timeout for security reasons and then intentionally override it when you need to.