RUN SQL STATEMENT nth times

You can use Cursor[^] or CTE[^].

ExXample - using CTE:

DECLARE @tmp TABLE(MyId int)
DECLARE @maxId int = 50

;WITH CTE AS
(
    --initial value
    SELECT 1 AS MyId
    --recursive part
    UNION ALL
    SELECT MyId +1
    FROM CTE
    WHERE MyId<@maxId
)
INSERT INTO @tmp (MyId)
SELECT MyId
FROM CTE

SELECT *
FROM @tmp

Result:

1
2
...
49
50

If this is for test data ONLY you can utilise a feature of the SQL GO statement which allows a batch to be run multiple times. You just enclose your batch between GO statements.

An example:

CREATE TABLE #Example (id int identity(1,1), dat nvarchar(20))
GO  -- This one is important otherwise it tries to create the table again
insert into #Example (dat) VALUES ('A'), ('B'),('C'), ('D'),('E')
GO 10
SELECT * FROM #example

This will give me 50 rows in the table. If you look at the output messages you can see what is happening

Beginning execution loop

(5 row(s) affected)

(5 row(s) affected)

(5 row(s) affected)

(5 row(s) affected)

(5 row(s) affected)

(5 row(s) affected)

(5 row(s) affected)

(5 row(s) affected)

(5 row(s) affected)

(5 row(s) affected)
Batch execution completed 10 times.

(50 row(s) affected)

Alternatively, using SELECT in the same way you have try

INSERT INTO #Example SELECT TOP 1 dat FROM #Example
GO 49

I can't remember where I first saw this but here is a link to an MSSQLTips.com article on the same Executing a TSQL batch multiple times using GO[^]

I cannot stress strongly enough that this technique should never find its way into Production code - it simply won't work.

SQL Server Utilities Statements - GO - SQL Server | Microsoft Docs[^]:

GO is not a Transact-SQL statement; it is a command recognized by the sqlcmd and osql utilities and SQL Server Management Studio Code editor.