Koreans use it when surprised by something impressive.
Yes. "놀라워요 (nollawoyo)" is polite and natural. You can also say "놀라워 (nollawo)" casually.
You can say "That's really amazing" — 정말 놀라워요 (jeongmal nollawoyo).
놀라워요 means "That's amazing / surprising." 놀랍다 (nollapda) = to be amazing/surprising, 어요 (eoyo) = polite. Common way to express amazement when seeing talent, hearing surprising news, experiencing something new.
1. Surprise: Impressive talent/news.
2. Admiration: Show appreciation.
3. Reaction: Create excitement.
That's amazing. Really?
That's really amazing!
Really amazing! (Casual)
Very amazing. (Formal)
• 대박 (daebak) - Wow / Amazing
• 신기해요 (singihaeyo) - Fascinating
• 멋져요 (meotjyeoyo) - Awesome / Cool