More information on Instagram having access to my person photos on my phones camera roll. If I give Instagram access to my iPhone 6 camera roll, does that mean my followers and people on Instagram, have access to it too? Can everyone see my camera roll photos on my phone?
It's not Instagram as a whole which needs access to your camera roll but the Instagram app. Without the access right, the app will not be able to access the camera roll if you want to publish a photo taken outside of the Instagram app.

But even with this access right granted, you still are in control of the photos you share with your Instagram friends. They will not be able to access photos in your camera roll.