then is a versatile word in English with multiple meanings:
1. At that time: "I was living in Shanghai then."
2. Next or after that: "First we'll eat, then we'll go to the movies."
3. In that case: "If you're tired, then you should rest."
4. In addition: "And then there's the matter of payment."
5. Used to emphasize a logical conclusion: "You think it's easy? Then you try it!"