If I do word for word translation, I say "日本語を学ぶためにお手伝い頂けますか?"
But I think this way isn't common and I can't come up with any sentences to express that in Japanese.
(If I must say, that is ”私の日本語学習にお手を貸して頂けませんか?" But I feel like that is awkward)
Sara's answer-日本語を教えてくれませんか is natural and usuful.