How can I download Microsoft office on my ipad

Microsoft have only recently released the single-install Microsoft Office App for iPad:

https://apps.apple.com/gb/app/microsoft-office/id541164041

Be aware that this App is a “lite” version of Office. The full versions of the Microsoft productivity Apps (Work, Excel, Outlook, PowerPoint, OneNote etc.) offer more functionality.

For both the Office and individual Apps, you will require an active Office 365 Subscription.

All of the apps themselves are free downloads from the App Store. Because your tablet has a screen larger than 10.1 inches, Microsoft requires you to have a paid Office 365 subscription to fully use their apps.