From your dashboard, click on the "Groups" link in the sidebar to see a list of your groups.
Find the group you wish to share an account with and click on the edit icon (a pencil) next to its name. This will take you to the "Edit Group" page.
On the "Edit Group" page, locate the multi-select list labeled "Accounts". Click inside this list to see a dropdown of all your existing accounts.
Select one or more accounts from the list to add them to the group. The selected accounts will appear in the list.
After you have finished adding accounts to the group, click the "Update" button to save your changes.
The selected accounts are now shared with all members of the group. Any user in that group will be able to see and use the 2FA codes for the shared accounts.