You can't sync different users to the same Google or Microsoft 365 email account or calendar.
Reason Email - Google & Office 365 does not allow this. It will break the integration of the first user that synced to the account.
Reason Calendar - The reason for this is that you would end up with duplicate events in your Google/Microsoft 365 calendar (that is, two users would create the same meeting in Google Calendar).
If you try to connect the same Gmail/Office365 email account to more than one Brite user, any other user using that account will get disconnected.
Each Brite user should integrate their own individual Gmail or Microsoft 365 account.
If you want multiple users to send emails from the same email account, you should set up an alias in each users account, the following article will explain how to do this: CLICK HERE.
Google Calendar Users
If you want multiple Brite users to see the same Google Calendar in the Brite Account Calendar, you should share the calendar in Google Calendar with each Gmail user, and then click 'Update Calendars' on the calendar integration page in Brite (CLICK HERE). Once you click this, the shared calendar should be available for all users in their Brite account.