VNC viewer let's you access your Pi remotely.
Barrier lets you use different devices as if they are separate monitors
GNOME for Pi
A project to get the popular GNOME desktop to run on Raspberry Pi OS.
Guide here: https://www.raspberrypi.org/forums/viewtopic.php?f=66&t=276512
Source code here: https://github.com/TerraGitHuB/gnomeforpi
Pi4 4GB with Manjaro ARM KDE