Linux remote desktop software?

[GodAtum]

At the moment I use Multiplicity and Windows 10. This is great because I can use the KVM feature to "remote desktop" into a remote PC.

But I cannot find a good equivalent for Ubuntu/CentOS

 

[GodAtum]

Teamview is way too expensive now, my budget is £30 per year. Also I need to be able to see the screen connected to the PC from my remote PC, kinda like remote support.