x11VNC on raspberry Pi OS – possible! VNC server for remote access or screen sharing.

sudo apt update  
sudo apt install x11vnc
sudo nano /lib/systemd/system/x11vnc.service
[Unit]
Description=x11vnc service
After=display-manager.service network.target syslog.target

[Service]
Type=simple
ExecStart=/usr/bin/x11vnc -forever -display :0 -auth guess -passwd password
ExecStop=/usr/bin/killall x11vnc
Restart=on-failure

[Install]
WantedBy=multi-user.target
sudo systemctl daemon-reload 
sudo systemctl enable x11vnc.service 
sudo systemctl start x11vnc.service 
systemctl status x11vnc.service