A family of Microsoft word processing software products for creating web, email, and print documents.
MS Word, then when I renewed it changed to MS 365!
I think you said elsewhere that you have an Android tablet. Is that correct?
If so, you will have to install the Word app from the Google Play Store. Sign in to the app using the Microsoft account info which is associated with your subscription.
With a subscription, you should be able to save documents locally on the device. If it is the free version, I believe all files are kept online, in OneDrive.