I recommend upgrading from 9.0 soon. The version is around 2-3 years old which is really old in the linux world.
Mandrake includes its version of YUM called URPMI. In the Mandrake Control Center there is a gui interface to it, or you can use it from the command line. Instructions for how to set it up and use it are at
http://easyurpmi.zarb.org