I have disk desiccation between c3-c6. What does that mean for an 18 year old male?

Disc fluids are. Drying up, as a result of this dryness and loss of fluid, the disc(s) degenerate (wear away) to a degree. Disc desiccation is the earliest visible sign of disc degeneration. Disc degeneration can range in severity from mild, moderate, to severe. Severe cases of disc degeneration can require surgery to fix the problem.
Well, YOU ARE LIKELY. Going to have some arthritic issues as life goes on. You may keep things at bay for the longest time with proper stretching, strengthening of the muscles surrounding your spine if you do it consistently. Report any numbness or tingling going down either arm to your doctor please.