Powershell script to add information to existing users from .csv

Hello all! What I am looking to do is add information to the Office field of all of my existing users. All of this information will be unique, so importing the information from a .csv would be preferred. I would imagine this is a pretty simple PowerShell script, but I am not very familiar with PowerShell and help would be much appreciated!!

Thank you in advance!!

--Russ