Unsure of how many Users to purchase with Zoom One Pro

I wish to schedule a 'family' Zoom meeting, with 8 participants, but it will last longer than the 40 minutes allowed by the basic membership.
In selecting the number of 'Users' in the Zoom One Pro package, must I enter 8 when selecting the number of users? Or, do I only select 1 for myself as the admin for the meeting? (All other participants are Basic Zoom members.)
Thank you for your guidance!