Download the Windows installer for the latest version of Virtual Engineer.
Download and run run the installer. Follow the steps presented in the installer until the application is completely installed. Then, continue to the next step.
Next, launch Virtual Engineer from the Start Menu or from the Desktop. During the first launch, a network access dialog is presented.
In this dialog, allow network access so your tablet is able to connect later. The correct setting depends on your network setup, but a safe bet is to allow Home Network.
At this point, the program can be seen running.
Take note of connection URL displayed by the program. Open the connection URL in a web browser on your computer. At the URL you will be greeted with a welcome screen. This confirms everything is working.
Finally open the same URL with a tablet. The tablet must be connected to the same network. Use a modern tablet that has an up-to-date web browser.
It's also a good idea to "Add to Home screen" or bookmark the URL for quick access later and to remove the browser frame.
Now all you need to do is to launch iRacing and start using Virtual Engineer.
Next time you want to run Virtual Engineer, just start launch the program and use your tablet's bookmark.