SQL Server 2019

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

create table T (CompanyName varchar(32), OrderDate date);
insert into T (CompanyName, OrderDate) values
('Alfreds Futterkiste', '1997 August'),
('Alfreds Futterkiste', '1997 October 1'),
('Alfreds Futterkiste', '1997 October 2'),
('Alfreds Futterkiste', '1998 April'),
('Alfreds Futterkiste', '1998 January'),
('Alfreds Futterkiste', '1998 March'),
('Wolski Zajazd', '1996 December'),
('Wolski Zajazd', '1997 December'),
('Wolski Zajazd', '1997 July'),
('Wolski Zajazd', '1998 April 1'),
('Wolski Zajazd', '1998 April 2'),
('Wolski Zajazd', '1998 February 1'),
('Wolski Zajazd', '1998 February 2')
13 rows affected

SELECT 
    CompanyName,
    year(Orderdate) as Yr, datename(month, min(Orderdate)) as Mnth,
    count(*) OrderTotal
FROM T
GROUP BY ROLLUP 
   (CompanyName, year(Orderdate), month(OrderDate))
order by
    grouping(CompanyName), CompanyName,
    grouping(year(Orderdate)), year(OrderDate),
    grouping(month(Orderdate)), month(OrderDate)


CompanyName
Yr
Mnth
OrderTotal


Alfreds Futterkiste
1997
August
1

Alfreds Futterkiste
1997
October
2

Alfreds Futterkiste
1997
August
3

Alfreds Futterkiste
1998
January
1

Alfreds Futterkiste
1998
March
1

Alfreds Futterkiste
1998
April
1

Alfreds Futterkiste
1998
January
3

Alfreds Futterkiste
null
August
6

Wolski Zajazd
1996
December
1

Wolski Zajazd
1996
December
1

Wolski Zajazd
1997
July
1

Wolski Zajazd
1997
December
1

Wolski Zajazd
1997
July
2

Wolski Zajazd
1998
February
2

Wolski Zajazd
1998
April
2

Wolski Zajazd
1998
February
4

Wolski Zajazd
null
December
7

null
null
December
13


SELECT 
    CompanyName,
    YEAR(Orderdate) as Yr,
    DATENAME(month, Orderdate) as Mnth,
    COUNT(*) OrderTotal
FROM T
GROUP BY ROLLUP 
   (CompanyName, Year(Orderdate), datename(month, OrderDate))
order by
    grouping(CompanyName), CompanyName,
    grouping(year(Orderdate)), year(OrderDate),
    grouping(datename(month, Orderdate)), min(OrderDate)


CompanyName
Yr
Mnth
OrderTotal


Alfreds Futterkiste
1997
August
1

Alfreds Futterkiste
1997
October
2

Alfreds Futterkiste
1997
null
3

Alfreds Futterkiste
1998
January
1

Alfreds Futterkiste
1998
March
1

Alfreds Futterkiste
1998
April
1

Alfreds Futterkiste
1998
null
3

Alfreds Futterkiste
null
null
6

Wolski Zajazd
1996
December
1

Wolski Zajazd
1996
null
1

Wolski Zajazd
1997
July
1

Wolski Zajazd
1997
December
1

Wolski Zajazd
1997
null
2

Wolski Zajazd
1998
February
2

Wolski Zajazd
1998
April
2

Wolski Zajazd
1998
null
4

Wolski Zajazd
null
null
7

null
null
null
13

CompanyName	Yr	Mnth	OrderTotal
Alfreds Futterkiste	1997	August	1
Alfreds Futterkiste	1997	October	2
Alfreds Futterkiste	1997	August	3
Alfreds Futterkiste	1998	January	1
Alfreds Futterkiste	1998	March	1
Alfreds Futterkiste	1998	April	1
Alfreds Futterkiste	1998	January	3
Alfreds Futterkiste	null	August	6
Wolski Zajazd	1996	December	1
Wolski Zajazd	1996	December	1
Wolski Zajazd	1997	July	1
Wolski Zajazd	1997	December	1
Wolski Zajazd	1997	July	2
Wolski Zajazd	1998	February	2
Wolski Zajazd	1998	April	2
Wolski Zajazd	1998	February	4
Wolski Zajazd	null	December	7
null	null	December	13