Ok, this works:
declare @qty int = 10; -- or pass as parameter
DECLARE @PrdNo INT = 100;
DECLARE @Output TABLE (prdno INT, DelID INT)
insert into Probale (PrdNo, PrdQty)
OUTPUT Inserted.PrdNo, Inserted.DelID INTO @Output
values (@PrdNo, @Qty);
;with cte as (select number, row_number() over (order by number) as num
from master.dbo.spt_values where number between 1 and @qty)
INSERT INTO dbo.tbl_PckDetail (prdno, Qty, delid)
SELECT ins.prdno, 1, ins.delId
FROM @Output ins
inner join cte on cte.num between 1 and @Qty;
Composable DML didn't work.