That's a nice start, Enid.
You need a definite article for the statment: 'I can teach you the English language'.
But more naturally we would just say, "I can teach English." or "I can teach you English."
And avoid using commas between sentences.
Maybe you can check out my profile if you want to become a professional teacher of English. Book a trial class. I can show you how I go about it and how I got to where I am.