If I have an icloud storage plan with my family can everyone see my photos?

No. See the following from Share an iCloud storage plan with your family - Apple Support

When you share a storage plan, your photos and documents stay private and everyone keeps using their own accounts with iCloud—just like when you have your own storage plan. You simply share the space available in the iCloud storage plan with your family members, so you only have one plan to manage.

You can of course share photos if you want to in the same way you could if not sharing storage plan.