
Hi, and welcome to Microsoft Q&A.
Yes, you can keep your current email address. However, one of you must subscribe to the "Microsoft 365 Family" plan instead of the Personal plan. "Microsoft 365 Family" allows for up to six family members to join the plan.
https://www.microsoft.com/en-us/microsoft-365/onedrive/compare-onedrive-plans
Feel free to post back if you require further assistance.
Craig