Do I use the demo link and edit to be what I need?  Is it only usable in the browser?  I downloaded the Github repository to try and use it locally, but can't find a way to do it.  Please help me, I'm so confused.

Edit: 

Yes, I did install Node.js.

Edit 2: 

I found the "Getting Started" guide, but I got this message when trying to follow the instructions: 

npm : File C:\Program Files\nodejs\npm.ps1 cannot be loaded  because running scripts is disabled on this system. For more information, see about_Execution_Policies at https:/go.microsoft.com/fwlink/?LinkID=135170 .

I've tried changing the settings as administrator like the instructions say; however, that has not helped or changed the situation.

Edit 3:

Actually, since I changed the settings as an admin, the error message seems to have changed.  Instead of saying scripts is disabled, it now says:

The file C:\Program Files\nodejs\npm.ps1 is not digitally signed. You cannot run this script on the current system. 

My system runs Windows 11 Pro, and is a 64-bit operating system.  Help?