Microsoft provides several pathways to use Office 365 without permanently "tethering" it to one machine's internal hard drive.
: The most truly "portable" version of Office is accessed via Office.com . These browser-based versions of Word, Excel, and PowerPoint require no installation and can be used on any computer with an internet connection. microsoft office 365 download center portable
If you need to install Microsoft 365 on computers that have limited or no internet access, you can create a "portable installer" on a flash drive. Microsoft provides several pathways to use Office 365