You can share your Microsoft 365 Family subscription with up to five other individuals if it is active.
You can install Microsoft 365 on as many devices as you like for each individual you share your subscription with, and you can sign in to five devices simultaneously.
Visit https://account.microsoft.com and follow the on-screen instructions to add a user to your subscription.
You will send an email with instructions to each person you add.
Their information, including the installs they are using, will show up on their My Account page once they have approved and finished the processes.
At https://account.microsoft.com, you can cease sharing your subscription with someone or delete a device they are using.