Some of your ideas are hard for me to understand, so I only try to correct your technical writing as my knowledge.
"Your familiesI always been interested in being a doctor as my future plan is to work in England but
I am not good enough in English so I have decided to enter the English language department."
Rewrite: Your families which I have always been interested in being a doctor. As my plan in future, I am going to work in England, unfortunately, I am not good enough in English, so I have decided to enter the English language department.
"My family is one best family in the world."
Rewrite: My family is the one of the best families in the world.
That all I can try,