Microsoft made this announcement “Microsoft Edge Canary channel available on Windows 7, Windows 8, and Windows 8.1.”
Visit the Microsoft Edge Insider site from your Windows 7, 8, or 8.1 device to download and install the preview today
Extra posts:
Supercharge Your Debugging with Remote Tools for Microsoft Edge 
Unlocking Productivity Remote Tools for Microsoft Edge 
How to Use Copilot in Microsoft Edge for Web Based Workflows 
How Enterprises Are Using Microsoft Copilot to Boost Productivity, Drive Innovation, and Gain a Competitive Edge 
Become Microsoft Windows tester-windows insider program 
WhiteBoard and New Preview Templates