I recommend one FB group for all of your "leads" ... ie this is the pond you are stocking with fish to go fish in later. So this group is where you would run 5 day challenges, announce your webinars and in person workshops and occasional power posts/ 5k in 5 day posts etc.
Then 1 fb event for each separate event with each event's specific details of date and time (and you can use the same zoom link) in the ONE group. But you will have 2 or 3 "events" in that one group. (I am in a group of parents with children across the veil and this one group is huge and they hold at least 3 - 5 online events each week and occasional in person events usually in Arizona so I don't go but I hear about them. But this group grows daily and you can always see what the upcoming events are and the topics and register to attend- super easy to do).