The PG light suspend feature works the same way in which a provider light suspend does, just for the whole practice rather than an individual. The PG light suspend feature won't affect any existing provider suspensions.
For example, if you were to un-light suspend an entire practice that already has any existing provider light suspensions, those provider light suspensions would not be lifted and you would then have to manually un-light suspend any providers from their respective provider settings.
To light suspend an entire practice (PG), navigate to Swords, DrChrono CRM, and select PG settings. Scroll down to the Primary Practice Group Settings. Check the box to the right of the Light Suspended option to light suspended the entire practice.
After checking the box, you'll need to enter a reason for the suspension in the field that appears.