The direct translation of 'thank you for everything' in Japanese is すべてをありがとう or 'subete no tame ni arigatōgozaimashita'.
Remember however, in a society which places such emphasis on respect and custom as Japan, this phrase may not fit the situation in which you find yourself.
You also need to be aware of whether you are thanking an old friend in an informal manner, or an elder family member, or a stranger, such as a shop assistant.
- A 'standard' "thank you" would be ありがとう or "arigatou," or, more informally, どうもありがとう or "doumo arigatou."
- In a situation requiring extra politeness or gratitude, you might say "thank you very much," in Japanese, どうもありがとうございます or "doumo arigatou gozaimasu."
- If you wish to thank, as politely as possible, someone for a service they have just performed, say ありがとうございました or "arigatou gozaimashita."
For another Blurtit answers to this question, check How Do You Say 'Thank You' In Japanese?
There are many Japanese language tutorials on YouTube demonstrating the correct way to say thank you, and when you should say it, such as this one: