I bought two baby turles two weeks ago, and they both have soft shells. What can I do to help them, they just started to eat this week.

Metabolic bone disease and pyramiding: A turtle with an inadequate calcium or Vitamin D intake, inadequate exposure to ultraviolet light, or disease of the liver, kidneys, or parathyroid glands may develop metabolic bone disease. This causes softening and malformation of the bones. The shells of turtles with metabolic bone disease are often deformed, with the rear area of the carapace pulled downward, and the marginal scutes pulled upward. Tortoises with metabolic bone disease may develop pyramid-shaped scutes. Metabolic bone disease can be fatal; turtles suspected of having this disease should be examined by a veterinarian. Husbandry and diet changes may be able to correct the calcium imbalance, but deformities are generally permanent.

Please read this article Turtle shell care

Maybe put them in heat so the shell can get hard. Me I don't know anything about one but maybe try it