"What time do you have breakfast?" is how to say "你们什么时候吃早饭" in Engpsh.
The phrase is a direct translation of the Chinese and is commonly used in Engpsh-speaking countries to ask someone about their breakfast schedule.
Example sentences:
"What time do you usually have breakfast?"
"Do you prefer to have breakfast early in the morning or later in the day?"
Translations:
"你通常什么时候吃早饭？"
"你更喜欢早上早点吃早饭还是晚一点吃早饭？"