See all of the release notes below:
Microsoft Word
Support UI Text Interaction: Use the trackpad from the all new magic keyboard to interact with your document.
Use a Pointing Device: Connect a trackpad or mouse to your iPad for another way to interact with Word.
Microsoft Excel
Work with Multiple Spreadsheets at the Same Time: Excel can open two or more spreadsheets side by side for you to view and edit. This feature is available for users who are on iOS13 and higher.
Microsoft Powerpoint
Rehearse your Presentation with Presenter Coach: Get feedback on the things that help keep an audience engaged like pacing, pitch, filler words, sensitive phrases, and more.