Documentation
Connecting a Google account lets FreeCRM work with Gmail, Google Contacts, and Google Calendar from inside the CRM.
In the current UI, open Settings and select Google. The Google area is split into three sections:

To connect the account:
Once connected, FreeCRM can:
When checking for incoming email, FreeCRM will save messages against an existing contact when it finds a matching email address. If you enable Auto Create, FreeCRM can create a new contact when one does not already exist, provided the incoming message includes both a usable name and an email address.
Connecting Google also enables Google Meet links on booking pages, without any further sign-in. See Video Conferencing.
If you use Scheduling and Booking Pages, synced calendar events are counted automatically when FreeCRM decides which slots are available. If you also keep other calendars in Google that are not synced into the CRM, enable the Google free/busy check in the booking page settings so those calendars are taken into account as well.