The iPad version of Microsoft Office must be upgraded. It will allow users to access new features of the trackpad and mouse in iPadOS.
Office update for iPad in the fall
Microsoft does not confirm the imminent arrival of support for the mouse and the trackpad, which uses the new cursor in iPadOS. However, it is understood that the relevant upgrade will take place in the fall (via The edge).
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Office 365 has become Microsoft 365 and there is a unified Office app for iOS. Despite this, the individual iOS versions of Word, Excel Powerpoint, and so on should remain available.