One possible version:

Dear Xiao Ming

   I’m glad to receive your letter. In your letter you asked me about how to learn English well. It is not difficult to learn English well if you know the good ways. Firstly you should listen to your teacher carefully and speak English as much as possiple. When you read English please read it widely because it will help you to learn it better. It is very important to learn it by heart too. Scendly You can improve your English by practicing writing in English. Thirdly watching English movies is also a good way to learn more English. This will help you to improve your listening and speaking skills as you will have a chance to listen to natural speech. I am sure if you study hard you will learn English well.

   I hope these ways will work well for you !

  Yours

                                        Xiao Hua

One possible version:

Dear Xiao Ming

   I’m glad to receive your letter. In your letter you asked me about how to learn English well. It is not difficult to learn English well if you know the good ways. Firstly you should listen to your teacher carefully and speak English as much as possiple. When you read English please read it widely because it will help you to learn it better. It is very important to learn it by heart too. Scendly You can improve your English by practicing writing in English. Thirdly watching English movies is also a good way to learn more English. This will help you to improve your listening and speaking skills as you will have a chance to listen to natural speech. I am sure if you study hard you will learn English well.

   I hope these ways will work well for you !

  Yours

                                        Xiao Hua