There are two ways the more complicated remote desktop way where the complete screen of a computer is transmitted ore the more native UNIX/Linux way to just use X forwarding having the application running on one computer and having its Gui window appearing on an other computer.
X forwarding is the native historical X way to have graphical terminals attached to a central computer.
X forwarding allows an X11 client (screen) to be connected to a X11 server using ssh.
Since security is a topic this might be disabled by default so check on the server the configuration file /etc/ssh/sshd_config
for:
X11Forwarding yes
Restart ssh to take effect, as for openRC /etc/init.d/sshd reload
To know what screen to use check echo $DISPLAY on the client. If nothing is shown fix it by running export DISPLAY=':0.0' or when logged in at the server with export DISPLAY='192.168.1.4:0.0' using the IP address of the client.
Then on the client commands as ssh -Y <server name>
/usr/bin/leafpad or ssh -X <server name>
/usr/bin/leafpad can be entered in the console to have a GUI window popping up.
An other sequence is ssh -Y <username>
@<server name>
and then typing in the commands as leafpad& where the & character puts the GUI application in background so additional application can be started from the console (as su and then starting commands as root as elogviewer&).