They do look like Barred Rocks, except for those feet.
I would wonder if you have Cuckoo Marans instead, because they have white feet (like your birds appear to) and otherwise look very much like Barred Rocks.
What they eat can also affect the color of the feet. For breeds with naturally yellow feet, plenty of green plants, or yellow corn as an ingredient of the chicken feed you buy, can make the feet much brighter yellow. No greens, and white corn or other grains in the feed, can cause the feet to be more pale.
But I think those feet are so thoroughly not-yellow that you are seeing a genetic difference (wrong foot color genes for the Barred Rock breed), not a feed-based difference.
They might be getting close to laying, given that the pullet's comb is getting bigger and pinker too. You might have eggs within a month or so