A recent addition to the massive list of over 2.8 million Android applications on the Google Play Store is the new Office by Microsoft, currently in active development and out for public testing. It bundles in Word, Excel, PowerPoint, amongst a whole lot more tools and nifty features for prosumers who need them - file sharing, document scanning, quick document format conversion, and the list goes on. Great idea, but we will see how it progresses as we get into 2020 and the official launch, whenever it happens.
As noted, the MS Office app is available as an early preview, i.e., insider build, including a dedicated beta update channel. To get just the preview version, clicking the Play Store link below and hitting the install button is all you have to do unless you want to go for an even more experimental build. If so, you can join the Office Mobile Android Preview group, and sign up for the beta afterwards.
Beware that I have been facing issues with getting any beta builds. There is a section on the Play Store page saying that the signup process is still in progress, no matter the amount of time that passed.