Can't you edit Word docs in browser in iCloud?

[BrightYellowStripes]

Because you can in OneDrive...

But when I click on a Word document in iCloud it merely downloads it to my MacBook!

Have I just wasted 79p?!

You should be able to, using what Apple call 'iWork for iCloud'. I've never used iCloud myself though so I don't know exactly how it works.