Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Greetings!
This is Tin, I'll do my best to help you. To upgrade, please go to https://account.microsoft.com/services and sign in your account that has the MS Office Personal on it. Please look for your subscription and click Upgrade or Switch to Family subscription. And to share your subscription or add your wife's on it, all you have to do is to sign in here: https://account.microsoft.com/services/office/sharing and select Share. You will have an option to send the invitation via email or you can create a link. Once you have sent it to your wife, she needs to accept the invite and once its accepted, she will be able to use the subscription. For more information, you can check this link: https://support.microsoft.com/en-us/accounts-billing/subscriptions/share-your-microsoft-365-subscription
Please let me know if you have any questions. I'm just here.
Thanks,
Tin