The following procedure will add a desktop environment and install remote desktop software on an Ubuntu cloud image.
sudo apt install gnome-shell ubuntu-gnome-desktop autocutsel gnome-core gnome-panel gnome-themes-standard gnome-settings-daemon metacity nautilus gnome-terminal dconf-editor gnome-tweaks yaru-theme-unity yaru-theme-gnome-shell yaru-theme-gtk yaru-theme-icon fonts-ubuntu tmux fonts-emojione xrdp
gsettings set org.gnome.desktop.background picture-uri ""
gsettings set org.gnome.desktop.background primary-color '#000000'
echo -e 'ubuntu\nubuntu' | sudo passwd ubuntu
sudo snap install code --classic
cat << EOF | sudo tee /etc/polkit-1/localauthority/50-local.d/45-allow-colord.pkla
[Allow colord for all users]
Identity=unix-user:*
Action=org.freedesktop.color-manager.create-device;org.freedesktop.color-manager.create-profile;org.freedesktop.color-manager.delete-device;org.freedesktop.color-manager.delete-profile;org.freedesktop.color-manager.modify-device;org.freedesktop.color-manager.modify-profile
ResultAny=yes
ResultInactive=yes
ResultActive=yes
EOF