If you don't have a good pronunciation it's simply because your mouth, tongue and speaking apparatus moves in a different way which you inherited from your mother tongue. Step 1: Understand which mouth motion any English sound requires. There are many videos on YouTube focusing on that. They explain in detail every step. Step 2: Practice slowly, speak slowly, you have to replay the sound you learned EVERY single time. It's like a dance you learn to do with your mouth: It requires exactly that motion. Step 3: Speed up Source: Not native but often praised for my excellent pronunciation. I spoke so much alone, driving in my car More on reddit.com

Firstly, the ea in beach is not the same as the i in bitch. Hence “each” does not rhyme with “itch”, and “feat does not rhyme with “fit”, “seat” doesn’t rhyme with “sit” etc. They’re completely separate sounds. Secondly, this issue exists in every single language on the planet. If you think English pronunciation is difficult I recommend having a look at a language like Irish: How do you pronounce this common Irish name?: Coaimhe. Or how is this word pronounced?: Beochaoineadh. You simply have to learn the patterns. But it would be a lot easier if you actually knew that ea is not a short i… The best option is to watch as much English language Tv as possible, or listen to the BBC World Service radio station as it has the clearest standard of English available 24 hours per day completely free of charge. More on reddit.com

What I do, most of the time, is speaking alone in English. It‘s a bit weird, but it helps a lot. You can try also to read aloud. I did it and helped me a lot. More on reddit.com

Atsueigo ( https://youtube.com/@atsueigo ) is a Japanese guy whose channel seems to have a ton of stuff about how to pronounce English naturally. Might be worth checking out his methods since they'd be aimed at people learning from Japanese. More on reddit.com