I am using latex, I installed texlive-* including texlive-latex, however, I don’t think it has beamer, so do I download it separately and install it manually or there is other ways to install it through yast?
I did a search of the OpenSUSE software page, and the package doesn’t seem to be there.
I also search on RPM Search for latex-beamer-2.22-2mdk, and found this: noarch.rpm.
Now, I didn’t install this package to test it because I don’t have the required packages to do so.
When you download the package, make sure that it is set to open with Install Software (default).
If it doesn’t work, feel free to say so, so we can find another method of installation.
Hope it works! 
$ rpm -qf /usr/share/texmf/tex/latex/beamer/beamer.cls
texlive-latex-2007-177.1