If I, wanted to learn to SPEAK English, I would go to a 100% English school. tutor or professional....... Not American.......Nor Canadian etc etc....... The dialect / pronounciation is going to be........American / Canadian........ Do you wish to end up speaking as an American / Canadian OR  AN  ENGLISH  person..........

I PERSONALLY, would not go to a  Foreign person and ask, ''Could you teach me English''....................Find a genuine ENGLISH native, that speaks and sounds ENGLISH................ Queens English !!