Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Go to https://account.microsoft.com/family and check if you are a family organizer. If not, you should see who is and ask family organizer to check and update Microsoft 365 subscription and share it with you.
If you are a family organizer, check here: https://account.microsoft.com/services status of your subscription. If it's active, you can install desktop apps (if included in your subscription).