Can someone give me some information on chronic kidney failure?

I’m 20 just diagnosed with stage 2 chronic kidney disease/failure but I don’t have my follow-up with my physician for another month. I’ve been feeling really anxious about this and I admit I dont know much about it. I only have the one kidney. Does the disease progress and if so how long does it take to go from stage 2 to end-stage? I’m too young for this lol