"How are you" is the English phrase that can be used to ask "你好吗".
If you want to ask someone how they are doing in a more formal or polite way, you can say "How are you today?" or "I hope you are doing well."
If you want to sound more casual, you can simply say "Hey, how's it going?" or "What's up?"
Remember to add a smile or nod to your question to show that you are friendly and interested in the other person's response.
