The purpose I went back to school was to ask advice of my English teacher, Mr. Zhang, who was my favorite teacher and friend.
The purpose of my visit to school that day was to meet my favorite English teacher, Mr Zhang to seek his advice on ????? (tell on what you sought advice)
Due to my bad performance in the College Entrance Examination,
He told me:"You know, you are good at English, so my suggestion for you is to choose a professional school of foreign languages. Maybe you can be an English teacher one day. It's a good profession for most girls."
... was it an overall bad performance and hew was suggesting you to specialize in languages as an option to divert your stream to something you do better? That is not clear and you better give a bit more details about that.
I knew my mom extremely wanted me to be a doctor like my elder brother.
I knew my mom's wish was to see me being a doctor like my older brother. Or
I knew my mom was very keen on seeing me becoming a doctor like my older brother.