SELECT DATEADD(DAY, -DATEDIFF(DAY, 0, [Order Date]) % 7, [Order Date]) AS [Week of],
COUNT(*) AS Count
FROM dbo.your_table_name
GROUP BY DATEADD(DAY, -DATEDIFF(DAY, 0, [Order Date]) % 7, [Order Date])
This code is exactly what I need! Thank you so much!