I have my pi plugged into a monitor with HDMI, and I want to use my laptop (running Ubuntu Linux) to control what it displays on the monitor through VNC. Currently, I can connect to the pi with VNC, but what I see in my laptop's VNC window isn't displayed on the monitor - instead, I just see the pi's command prompt. I want the image of the pi's desktop that I see on my laptop to display on the monitor, and I want to be able to control it with my laptop's mouse and keyboard - in short, I want the pi to mirror the VNC client. I'm using Remmina on the client laptop but if there's a better program let me know. In your response, please lay out all the steps and be as painfully specific as you can be - I'm a newcomer to all this.
A similar question to mine was asked here, but I found the answers unclear.