create procedure myProcedure @Query  varchar(max)
AS
begin 
declare @sql nvarchar(max)
set @sql = 
' select
 '+ @Query +'
 from mytable ' 
exec (@sql) 
 end

with c1 as (
select *,ROW_NUMBER() over(partition by storekey order by tssid)rn from (values
(1,1),(1,2),(2,1),(2,2),(3,1)
)v(storekey,tssid)
)
,c2 as (
select *,ROW_NUMBER() over(partition by storekey order by tssid)rn from (values
(1,1),(1,3),(2,1),(2,2),(4,5)
)v(storekey,tssid)
)

select  *from c1 
full join c2 on c1.storekey = c2.storekey and  c1.rn=c2.rn
order by 1,2,3,4

create procedure SelectFromStudent
(
 @Query  varchar(max),
 @TblName varchar(50),
 @Age  tinyint
)
AS



 declare @sqlQuery varchar(300);

 set @sqlQuery='select ' + @Query +' From '+ @TblName+' Where Age='+@Age);