A:AnswerOffice Home & Student 2021 requires one of the three most-recent versions of macOS in order to operate correctly. When a new major version of macOS is released, that macOS, and the previous two versions, will be supported. As macOS 10.13 falls outside of this category, it is not currently supported.
A:AnswerPeggy this is only for your one computer, laptop. I bought one for my wife and one for me as we are used to using Word on our projects. I hope this helps you in your decision.
A:AnswerIf you purchased the Home and student version(a one time purchase fee) it is only good for 1 computer. If You are paying fo the monthly renewal/subscription service I believe you can use it on up to 5 computers.