Q. How much space does downloading Microsoft Office 365 take up on my device?

To download Office 365 you typically need between 2-4gbs of free space on your device.

It can vary though, with updates and even depending on your device.

You can have a look at some more info on the Microsoft Website here:

What is the size of Office 365 when you download it?

Download sizes for updates to Microsoft 365 Apps

Microsoft 365 and Office Resources