Microsoft Office 365 icons greyed

I recently upgraded from a 2013 macbook air to a macbook pro. Microsoft Office in its older version enabled on the macbook air, no longer worked on the new macbook pro. The icons are greyed out on the launch bar. I did buy and download the new version of Microsoft Office 365 and have down loaded the apps as well.

How do I proceed?

Removing the greyed out icons.

Replacing those icons with new ones.

If I were to remove the old icons does this also remove the word docs and excel docs as well?

Thanks for any help,

Mary