Based on the level of respect or formality, you can say "I am a salesperson." in Korean in 3 ways:

• Informal: na-neun panmaewon-iya. (나는 판매원이야.)
• Formal: na-neun panmaewon-iyeyo. (나는 판매원이예요.)
• Very formal: jeo-neun panmaewon-imnida. (저는 판매원입니다.)