This question makes more sense when you consider the questioner's origin.

What kind of question is that? It's like asking, "Who is a better parent -- a mother or a father?" Or "Who is a better student -- a male or a female?"

Curiously, i was, for a second, wondering if you were asking about the 3rd person singular. Do we use HE or SHE or IT, when we refer to a person whose gender is unknown..

The better way to ask that question is "Which gender is the best to talk and practice with in English?"" And I don't think it comes down to gender, but if you like, I am a teacher and would be happy to help you!

Maybe it would be better to choose a person rather than a gender - or do we think all men are of one character and all women of another? And of course that person has to want to choose you too. Perhaps it would be good to choose someone you like, who likes you, who wants to learn what you can teach? Of course, you will do better with a teacher who will focus on your learning needs and interests, though it will cost something.