Waht kind of a file it is? Is it a RPM, Deb, .tar.gz or a .bin
Since you are using SuSE I'll assume you have a RPM. This would install it
rpm -ivh download_file.rpm
replace "i" with "U" if you want to upgrade. And of cource replace the "download_file.rpm" with your file name.
If you don't have a .rpm things are a little different.
And after you install it if you can't execute it by entering "firefox" in a terminal. Try
This will search a part of your file system and tell you where it is.