SQL Server 2017

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create table MyTable (Id int, GeneratedAt datetime)

insert into MyTable values
(123,'2019-11-02 15:03:07.117'),
(124,'2019-11-02 15:03:42.040'),
(125,'2019-11-02 15:03:56.887'),
(126,'2019-11-03 11:53:47.720'),
(127,'2019-11-03 11:58:59.333'),
(128,'2019-11-03 12:02:26.480'),
(129,'2019-11-03 12:04:06.550'),
(130,'2019-11-03 14:26:02.547'),
(131,'2019-11-05 12:42:48.307'),
(132,'2019-11-05 12:43:13.437'),
(133,'2019-11-05 12:43:24.787'),
(134,'2019-11-05 12:43:50.030'),
(135,'2019-11-05 15:35:47.057'),
(136,'2019-11-05 16:33:39.057'),
(137,'2019-11-05 16:38:40.717'),
(138,'2019-11-06 12:58:49.807'),
(139,'2019-11-06 12:59:02.367'),
(140,'2019-11-07 10:59:47.350');

set  DATEFIRST 6;
with CTE as
(
SELECT     
          DATEPART(MONTH, GeneratedAt) AS 'Month',  
          DATEPART(WEEK, GeneratedAt)- 
          DATEPART(WEEK, DATEADD(MM, DATEDIFF(MM,0,GeneratedAt), 0))+ 1 
          AS 'Week',
          COUNT(*) AS 'Visits'  
FROM     MyTable  
where DATEPART(Month, GeneratedAt)=DATEPART(Month, GETDATE()-2)   
GROUP BY  
          DATEPART(WEEK, GeneratedAt)-
          DATEPART(WEEK, DATEADD(MM, DATEDIFF(MM,0,GeneratedAt), 0))+ 1 ,
          DATEPART(MONTH, GeneratedAt)
)
select isnull(CTE.[Month],DATEPART(Month, GETDATE()-2)) as [Month],
      AllWeek.wk as [Week],
      isnull (CTE.[Visits],0) as Visits
from CTE
right join (values(1),(2),(3),(4),(5),(6)) as AllWeek(wk) 
on AllWeek.wk = CTE.[Week]
ORDER BY     
[Month],[Week]

Month	Week	Visits
7	1	0
7	2	0
7	3	0
7	4	0
7	5	0
7	6	0