when i trying to install window hard disk not found

Welcome, Rohit_26!

You'd need to make sure that the HDD is mounted properly and even try re-seating all the connections to it. Once you do that, go into BIOS and make sure that the SATA mode for the hard drive is either set to IDE or AHCI (what @Emerald asked of you) and even try switching them to see if that will help the OS detect the HDD. I'd also suggest you use a Win 7 tutorial for the step-by-step of the installation.

Hope this was helpful. Good luck! :)
SuperSoph_WD