Learning any other language isn't an overnight process. Constant practice makes perfect.

Let me help you ;)

A question mostly asked by my Japanese students. First decide which English is the right English for you. There are countless versions and most are not so difficult. Once you have decided if you want a British English, an American or Australian English, or any of the many other forms, try to find a role model, like an actor or a politician you would like to sound like. Of course it can also be simply a teacher. Then listen and try to copy him. Reading out loud helps and also listening to podcasts read by the same person. If you try to copy from many people you get confused, as every person sounds different. As a man you should try and copy a male voice. It will sound better to you, nearer to your own voice. Another way is to read out loud and record your reading (Ideally a text that also has a podcast). Then listen to your reading and compare it to the podcast. Good luck. (PS.: You should not worry too much about pronunciation. As long as people understand you you will do fine. There is no "one" way to pronounce something only. Like in Japanese it depends on the area how something sounds. Think of Kanto or Kansai vs. Tohoku-ben!! All is Japanese and none is incorrect, but they do sound very different.