i want to install oracle on mac os x lion

Oracle what? They only make a Java runtime for Apple to install with OS X. Their other software will not run on a Mac. It's mostly Windows and Unix.

I don't believe Oracle makes a version for the Mac. Ask tech support at Oracle. Or you can try with other database applications for the Mac such as:

FileMaker Pro

Excel from Office 2011 for OS X

MySQL

These are three good ones. There is an Access-like database program as part of Libre Office that is compatible with OS X. There are many OS X compatible applications for accessing and using Oracle databases, but not creating them.