" how can I install them and can I install new programs without it?"
You can completely maintain your rpm packages with command line rpm. Read:
Another install program that is more convenient but less versitile than rpm is kpackage. Set your *.rpm mimlink to kpackage and then whenever you click on a rpm file it will open in kpackage. If you do not have kpackage installed it is one of the programs in the kdeadmin package.
Be prepared. Create a LifeBoat CD.