Copy some lines from one file to another

Hello Gurus,

I am extremnely new to scripts

{\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\fnil\fcharset0 Courier New;}{\f1\fswiss\fcharset0 Arial;}}
{\*\generator Msftedit 5.41.15.1507;}\viewkind4\uc1\pard\f0\fs20 ProMAX Data Export: Parameter Table - PreSTM_VELO_RMS\par
Area: 3d Line: khag-matim-sps\par
CDP X Coor Y Coor Inline
----------------------------------------------------------------
17533.0 3239887.5 1081418.2 1020.0

up to the six line it is the header of the file ,Whic may be the 10 in another file so I have to ask user that upto when your header is and say user type 10 in the above file it will be 6 then it should copy upto 6+1 in the another file.

can any body please guide me on this ?

Thanks & regards