Sharing Microsoft 365 with family member. No option to share

Is your Microsoft account the "owner" of the Microsoft 365 Family subscription, that is, the subscription is associated with your Microsoft account? In that case, you should be able to follow the steps for inviting family members; see https://support.microsoft.com/en-us/office/share-your-microsoft-365-family-subscription-b389b9ce-3ae3-4a82-9017-39d79972fcba . The people you invite should then follow the steps at https://support.microsoft.com/en-us/office/someone-invited-you-to-share-their-microsoft-365-subscription-6a6c098e-1934-4436-9a94-69c92590da5b .

Thank you. I am the account owner. However, I am not shown as the family organiser - that is one of my sons in the group. I am trying to re-establish access for another son in the family group. He is shown as being a member. How can he login and access 365?

Thanks for the follow-up. I suspect that you will have to be added as an organizer in your family group. For more, see https://support.microsoft.com/en-us/account-billing/add-people-to-your-family-group-4a07b974-8103-16ad-6ea2-46549ca19e03 .