custom paging using store procedure in sql server with row number

input parameter for sp

, @PageSize INT = 10

, @PageIndex INT = 1

store procedure definitions

SELECT XYZID, XYZType, InCylinder,InSystem,XXXX
FROM (
SELECT XYZes.XYZID
 , XYZes.XYZType
 , ISNULL((SELECT SUM(TABLEPQR.XYZVolume) FROM TABLEPQR WHERE TABLEPQR.XYZID = XYZes.XYZID AND TABLEPQR.AssetTypeID IN (1, 3) ), 0) AS InCylinder
 , ISNULL((SELECT SUM(TABLEPQR.XYZVolume) FROM TABLEPQR WHERE TABLEPQR.XYZID = XYZes.XYZID AND TABLEPQR.AssetTypeID = 2 ), 0) AS InSystem
 , ISNULL(
  ISNULL((SELECT SUM(TABLEXYZ.XYZVolume) FROM TABLEXYZ WHERE TABLEXYZ.XYZTypeID = XYZes.XYZID AND TABLEXYZ.Activity = 'XXXX'), 0)
  +
  ISNULL((SELECT SUM(TABLENNN.XYZVolume) FROM TABLENNN WHERE TABLENNN.XYZTypeID = XYZes.XYZID AND TABLENNN.Activity = 'XXXX'), 0)
  , 0) AS XXXX,
ROW_NUMBER() OVER (ORDER BY XYZID) AS RowNum
FROM XYZes ) AS SOD
WHERE SOD.RowNum BETWEEN ((@PageIndex-1)*@PageSize)+1
AND @PageSize*(@PageIndex)

select @RecordCount = COUNT(*) From XYZes
return @RecordCount