the icon for network manager is not appearing on panel.
this is becuase by default network is managed with traditional method with ifup, to change this we have to change it to user controlled network manager
go to yast > Network Devices > Network Settings > Global options
select User controlled with NetworkManager
by default traditional method with ifup is selected
once you did that network manager icon will be added to panel, now you can set up your network using this from your desktop