Years ago you could log in online to watch movies you purchased. Now with movies anywhere...

Digital movies purchased form the Microsoft store are only streamed to your console, there is no download option so you require a connection to view them.

On a Windows 10 PC you can use the Movies and TV app to download them for offline viewing.

For more information, see Microsoft Store: Movies & TV and Movies Anywhere.

Correct, and just to add a reference point,
this is covered on this page, here. It specifically says:

• Purchases from Movies & TV are not downloaded to your console but are streamed over the Internet to your console or other Movies & TV-compatible devices. For more information, see Microsoft
  Store: Movies & TV.

Now, what you CAN do with that, is sign up for
Movies Anywhere. Then all of your eligible Microsoft Movies & TV content will sync over with Movies Anywhere and then you could use a service that DOES allow you to download and watch the movie offline, though through a very cursory search does not look
like there is an option on Xbox One? Vudu is a Movies Anywhere app, though I have never used it to see if you can download titles for offline play.

Correct, and just to add a reference point,
this is covered on this page, here. It specifically says:

• Purchases from Movies & TV are not downloaded to your console but are streamed over the Internet to your console or other Movies & TV-compatible devices. For more information, see Microsoft
  Store: Movies & TV.

Now, what you CAN do with that, is sign up for
Movies Anywhere. Then all of your eligible Microsoft Movies & TV content will sync over with Movies Anywhere and then you could use a service that DOES allow you to download and watch the movie offline, though through a very cursory search does not look
like there is an option on Xbox One? Vudu is a Movies Anywhere app, though I have never used it to see if you can download titles for offline play.

Thanks for adding the extra info.

I would point out though that Movies Anywhere is only available in the US.

Hi! the only browser is microsoft edge, but there are a lot of apps that allow you to see video content. you can also use a movies anywhere account if you have it https://support.xbox.com/en-US/xbox-one/apps/watch-movies-anywhere-purchases-in-movies-and-tv

Hi again Archer Dell,

This what I found on this issue fromhttps://support.xbox.com/en-US/xbox-360/apps/buying-and-renting-videos-on-xbox-360

If your using Xbox movie app:

Note Unlike a movie that you buy, you must view a movie that you rent on the device you rented it for (for example, the Xbox 360 console, a computer, or a Windows Phone)

However I know Microsoft allowes you watch rented movies via a app called Movie Anywhere. If you purchase a movie on your account and if was produce by a movie studio they team up with>>>you can watch your rented movies there. I used this app in the past
and I had no problem watching my rented movies on there. Here more about ithttps://news.xbox.com/en-us/2018/08/06/microsoft-movies-tv-now-supports-movies-anywhere/.