1. Allow Ubuntu to share desktop:

First, [Allow other users to view your desktop] –> Cancel [Must confirm eah access] –> Set [Required password].

2. Install the base dependencies.
1 | sudo apt-get install xrdp vnc4server xbase-clients dconf-editor |
3. Cancel requlre-encryption
- Open
dconf-editor(Type dconf-editor in terminal.) - Find
org->gnome->desktop->remote-access - Cancel
requlre-encryption.

4. Usage:
- Open your os
dash(Press [alt] key.) and searchRemmina Remote. - Input the IP of PC you wanna remote.

- Choose the vnc-any method.
- Input IP and Password(The password is up to your configuration where you set in Desktop Share.).

- Now Enjoy your Remote.
- If you wanna use it in Windows. Search for
远程桌面连接OR Press [win + R] and InputmstscRun it. Then your next step is as same as linux.