Im 21 male, i am about to work as a seaman but the result of my medical xray was i have a mild dextroscoliosis, could this be okay or can i still work?

Likely non-issue: Many people have mild scoliosis and don't even know it unless they happen to have an x-ray. In the absence of back pain, it is unlikely that your physical activity would need to be limited. However, this mal-alignment does put you at increased risk for injury, so your candidacy as a seaman largely depends on your re acquired duties. The marine industry may have very specific restrictions.