OpenSuse uses RPM correct?
Yes and No.
SUSE has a history that goes back nearly as far as Redhat (RPM is Redhat Package Management), and right from the start, they started putting their own "stamp" on things.
Where RPM uses/used YUM (Yellowdog Update Modifier, now deprecated), and DNF (Dandified YUM), openSUSE uses zypper to install, update and upgrade.
A guide to bookmark is the Pacman/Rosetta, brought to us by our friends at Arch
... which will help you to implement a number of the common commands.
Which DE do you use for OpenSuse?
The standard is KDE - I do not know of an alternative, although I could be mistaken (happens every 100 years or so
). I would be surprised if there was not a spin somewhere, with alternatives DEs. Gecko which is based on openSUSE has MATE and Budgie, amongst others. I have the MATE as well.
Be aware, too that openSUSE is one of very few Linux Distros that does not provide for a Live "try before you buy" scenario. It is install or nothing. I can provide articles if you want a read, or else search under eg
openSUSE no Live option
And I will NEVER live that down I see
I might forget it in a century or so, my memory is not what it was the Millennium before last
I am going to include how to install TS in openSUSE in my Timeshift article
shortly, or sing out if you need help.
BTW my experience is limited to the Rolling Release, Tumbleweed, have not used Leap yet.