Refer the below SQL Test query for your reference and call it for you report SP or Query you just need to pass Parameter by selecting M for Last Month and W for Last Week.
SQL
DECLARE @FilterMonthOrWeek CHAR(1)
SET @FilterMonthOrWeek = 'M' -- For Month Wise
SET @FilterMonthOrWeek = 'W' -- For Week Wise
SELECT SUM([countt]) AS TotalCount
FROM [Customers]
WHERE (@FilterMonthOrWeek = 'W' AND DATEADD(day, DATEDIFF(day, 0, [date_save]), 0) >= DATEADD(day, -((DATEPART(dw, GETDATE()) + @@DATEFIRST) % 7) - 6,
DATEADD(day, DATEDIFF(day, 0, GETDATE()), 0)) AND
DATEADD(day, DATEDIFF(day, 0, [date_save]), 0) <= DATEADD(day, -(DATEPART(dw, GETDATE()) + @@DATEFIRST) % 7,
DATEADD(day, DATEDIFF(day, 0, GETDATE()), 0)))
OR (@FilterMonthOrWeek = 'M' AND DATEPART(m, [date_save]) = DATEPART(m, DATEADD(m, -1, getdate()))
AND DATEPART(yyyy, [date_save]) = DATEPART(yyyy, DATEADD(m, -1, getdate())))