The Windows Update being release 15th Jan 2020 will automatically install the new Chromium based Edge browser
Usefully MS are providing a method to prevent that happening, if you so choose.
The process is a bit clunky, but then if it was easy, everyone would be blocking Edge!
"...On January 15, 2020, Microsoft is expected to begin the automatic rollout of the new version of Microsoft Edge based on the Chromium engine through Windows Update on devices running the Windows 10 April 2018 Update (version 1803) and newer releases to replace the legacy version.
Although it's recommended to switch to the new version of the browser, there could be a lot of reasons that you may want to skip it.
For instance;
You work in an organization, and you need to comply with your network environment policies.
You use another web browser, and you're not interested in Edge Chromium.
You're comfortable using the legacy version, and you want to wait a little longer to update.
Whatever the reason may be, you can use the Microsoft Blocker Toolkit or the Registry to prevent Windows 10 from installing the new version of Microsoft Edge through Windows Update automatically...."
Here's how -
Link to Windows Central