Can I sync multiple calendars to Tana?
Currently, Tana only accepts one calendar account which it can sync events from. We're hoping to add support for multiple calendar accounts in the future, but in the meantime, there is a workaround where you can make events from other accounts sync to a single account, which then could connect to Tana.
To connect a Google account's calendar to another, go to the settings of the calendar you want to add to the primary calendar. Under "Share with specific people and groups", add your primary account and allow them to "make changes and manage sharing".
Now go back to your primary account. Once properly linked, you'll see the calendar appear under "My calendars" in Google Calendar, not "Other calendars".
Then go to Tana and Settings > Google Calendar sync > General config, you should be able to select it from the list of synced calendars.