Hi Pam, welcome. Have you had your bees awhile or are they new colonies, and if so how did they start (package or nucleus)? Is there a nectar flow on in your area? How full are the brood boxes? Are your queens laying well?
What I’m getting at is the many factors that lead to bees having the wherewithal to start storing extra food. After that point, with brand new Flow frames they have to seal up all the seams before storing nectar in them. If this is your first season, to be honest you shouldn’t expect to have a harvest. A good outcome would be that your bees build up to a good size to overwinter.
If your colonies are new, brood boxes not full, and/or there is not a good nectar flow on you shouldn’t have supers on yet. If all is going well, then take a look at this video for some more tips: