for loop in sql or Query to Clustered Index Table Slow in While loop in SQL Server Stored Procedure

DECLARE @i int = 0

WHILE @i < 20
BEGIN
    SET @i = @i + 1
    /* do some work */
END

or

DECLARE @i INT = 0;
SELECT @count=  Count(*) FROM TABLE

WHILE @i <= @count
BEGIN

    SELECT * FROM TABLE
    ORDER BY COLUMN
    OFFSET @i ROWS   
    FETCH NEXT 1 ROWS ONLY  

    SET @i = @i + 1;

END

or

DECLARE @cnt INT
SET @cnt = 0

DECLARE @ID INT
SET @ID = 10001

WHILE (@cnt < 500)
BEGIN
    SELECT TOP 1 @ID = ID
    FROM mytbl
    WHERE ID > @ID

    SET @cnt = @cnt + 1
END