Limit access to a single machine

In my organization we are in the process of migrating users to SharePoint Online. Let's direct users to use the SharePoint online file service.
But for some computers that have multiple people access to use some files, let's create a generic user. This will only be used to access spreadsheets for example. How can I make this generic user only log on to a specific computer?
We currently have the Office 365 E3 license.
Thank you for your attention.