As your organizational needs change, you can buy more licenses to accommodate new people, or reassign licenses to other users when someone leaves your organization. After you buy a subscription, you create accounts for people in your organization, and then assign a license to each person.
When you buy a subscription, you specify the number of licenses that you need, based on how many people you have in your organization. You can see what comes with each product on the Microsoft 365 for small and medium-sized businesses page.
The applications and services that you receive as part of your subscription depend on which product you purchased, such as Microsoft 365 Apps for business or Microsoft 365 Business Standard.
When you buy a subscription to Microsoft 365 for business, you sign up for a set of apps and services that you pay for on either a monthly or an annual basis.