To access submitted group assignments, navigate to the Grade Centre > Needs Marking in the Control Panel

In Needs Marking, you can choose to filter by item and select the appropriate assignment, or by user to begin with a specific group submission.

Click on the assignment menu and choose Grade All Users or select a group name in the User Attempt column to begin grading on the Grade Assignment page.

Alternatively, begin from the Grade Centre and click on the yellow exclamation mark Needs Grading icon. All group members' cells display the Needs Grading icon, regardless of who submitted the group assignment.