Office 365 (if you mean that) is linked to a Microsoft account indeed.
Compare it with a credit card. If you cancel your creditcard account, you can't use your creditcards linked to it any more.
But Microsoft could have given you a free license, if they wanted.
Recently closed and deleted outlook email account associated with Microsoft office due to calendar issues. Created new outlook account and was using Microsoft office without any problems. Updated Microsoft office and rebooted computer. Microsoft office asked for activation of office subscription. Attempted to undelete outlook account but could not. Office was not available with new outlook account. Support could not retrieve old account. Told by support that only option left was to purchase another office subscription to use Microsoft office. I found out that Microsoft office is link to your email account and once deleted it will not function. I had to purchase another office subscription. Please be aware of this issue with office subscriptions. Costly lesson!