There are several ways to update openSUSE Leap. However there is one way that has served me the best over the last 10 years using openSUSE. And this is via the YaST Software Management graphical GUI interface. .
Other ways to update openSUSE Leap are.
The command line Zypper method works just as well as the method described in this article. However not everybody is comfortable with using the command line CLI interface. .
YaST online update is good for patching openSUSE official software however this doesnt cover software patches from third party repositories such as Packman or Google Chrome. .
KDE Plasma Software Updates does find all software that needs updating however it isnt smart enough to resolve all issues So sometimes a software update will fail because of missing dependencies or package conflicts. .
Using YaST Software Management for updating an openSUSE Leap system is therefore the most reliable way of doing it. The first step in this method is to open YaST and then open Software Management.