What all requirements needed?? what all steps to follow in detail??
You want to host a web page from your PC? Install XAMPP
Step one, install windows 7.Step two, install whatever server software you want.
How to make a Windows 7 Computer a server? Install a server OS on it! Which OS depends on your needs, and what you want the server to do. You will have no end of troubles trying to hack a W7 computer into a server.
The answer depends what kind of server you want to build, and what you want the server to do. Keep in mind Win7 has a limit of 20 simultaneous connections. That can be 20 users with one file each, or 2 users with 10 files each. Not ideal for a server.
Of what ? Web ? Put a LAMP stack on it.