Encrypts your connection: Encrypts your internet connection to help protect your data from online threats like hackers.
When using Microsoft Edge Secure network, your data is routed from Edge through an encrypted tunnel to create a secure connection, even when using a non-secure URL that starts with HTTP. This makes it harder for hackers to access your browsing data on a shared public Wi-Fi network.
Helps prevent online tracking: By encrypting your web traffic directly from Microsoft Edge, we help prevent your internet service provider from collecting your browsing data like details about which websites you visit.
Keeps your location private: Online entities can use your location and IP address for profiling and sending you targeted ads. Microsoft Edge Secure Network lets you browse with a virtual IP address that masks your IP and replaces your geolocation with a similar regional address to make it more difficult for online trackers to follow you as you browse.Microsoft support document
This sounds too good to be true. The service is provided by Cloudflare. And there is a catch:
Is free to use: Get 1 gigabyte of free data every month when you sign into Microsoft Edge with your Microsoft Account. See below instructions to turn on your Microsoft Edge Secure Network.
I burn through a few gigabyte every day. We will see. Maybe they will provide more with Microsoft 365.