It's been like this for a few months, slowly increasing the grey, but under its green. It also seems to have roots I think growing from the joints, I have no idea what to do with it
Your plant may be overwatered. You can repot it in soil labeled for cacti and succulents to ensure good drainage. Let the plant dry out between waterings.
Also, like Christmas cactus, the roots between segments are aerial roots and are common in epiphytes. You don't need to do anything with them. See article below.
Here is the proper care for an Easter cactus: