You will NOT be able to download Office 365 on the Brown-Guest wifi/if offsite connect to VPN first.) Your computer will need to be on the Brown network for initial activation and a periodic check-in. The non-365 versions are the same software, but for Brown-owned computers.
Microsoft Office 365 allows students, Brown-paid faculty, and staff to download and install Microsoft Office (Word, Excel, etc.) on up to 5 personal computers and use it while they are an active member of the Brown community.