have you actually asked your teacher how to improve it? we don't really have much a reference point on their expectations so
this topic should be pretty easy to approach objectively if you just speak objectively
like what's the general idea of what you're doing currently? to me, as long as you don't make the statement personal, it's actually
more difficult to make a thesis which makes a strong, biased claim for argumentative purposes
the thesis was something along the lines of, "parents and peers both affect the decisions of people in fields such as advice and wisdom." i don't understand how that's biased.
i don't see how it is either. perhaps a better way to word it would be something like "two ways in which parents and peers affect people's decisions are by providing advice and wisdom," which concedes an incomplete explanation. if you haven't already, just speak to your teacher about their expectations with this cus that's a bit ridiculous. i understand when english teachers try and be strict like that, but if you don't understand what they actually want, that's a problem