Number groups can be helpful in multiple scenarios! Don't overthink this, it is simply a way to organize your phone numbers to make your life easier! See the guide to learn more.
Start by going to "phone system" in your menu then "Phone numbers". Find "Number groups" on the right of the page and click the blue addition symbol.
Naming your number group: You could make a group to place numbers in specifically for the morning hours, evening, by the area code etc. The example below shows the user making a new group for morning numbers so that they can use different numbers at different times of day so they are giving some of their other numbers a break. They also already have an existing number group named "480 Group" for all of their 480 area code numbers.
Destination: The "destination" is where you'll choose what happens when a contacts calls you back.
You could connect a voicemail, an inbound call queue etc.
Click "save" when done. These will now be the settings for any phone numbers you decide to add to this group in the future.
Watch the above video to see different scenarios you might utilize number groups!