Your cactus is dead. You cannot bring it back to life. Throw it away, and learn from your mistakes. The first mistake is buying a plant which has been artificially painted, so the next time do not buy a plant which is already under stress like this.
Your second plant is still living and in the family Crassulaceae, likely an Echeveria or a close relative (not a cactus) but it's hard to tell because it's grossly etoliated. I personally would throw it away as well. If you insist on trying to save it, give it a very dry, rocky, soil with infrequent watering (allow it to dry completely out between waterings) and increase both the quality and duration of light it receives.