I don't know where you could have found an RPM for apache, but to install any rpm you should.
1. cd to the directory the rpm is in
2.
rpm -ivh filename
i-stands for install v-stands for verbose h-stands for hash to show progress, do # rpm --help for all options
I personaly don't like RPMs even though there are extreamly easy... I suggest you build apache from source because it is full of options
