New
#1
No, it's not a Microsoft app. For a start, it clearly states that it is a product from Total AV. And no, it's not an app from the Store, its a 3rd-party extension for Edge. Go to edge://extensions/ and click Get Extensions for Microsoft Edge and you'll see it there.
It's sitting between Mcafee Web Advisor and Grammarly for Microsoft Edge in the 'Most popular' section.
And if you click on it there, you'll go to that page you complained about. There's another page just like it for AdBlock Plus...
Adblock Plus - free ad blocker - Microsoft Edge Addons
...and one for each of the 111 addons (none of them from Microsoft) that you'll find if you type 'adblock' in the search box.
No, what is worrying is not the content of what pops up, that's legitimate and has a microsoft.com web address. Just because Microsoft officially list it as an addon for Edge doesn't mean they endorse it, but it does mean that as far as they know it's safe to offer it to you (as should be all the others).
What is worrying is that the sites you are visiting can tell Edge to show you that page. It's not a scam, but it is over-aggressive advertising (and probably what propelled it into the 'most popular' category).
Thanks to you both I finally got it after a bit of fiddling around with it Plus it popped up on my main laptop too so my network is working fine too!!