how to write the best in chinese?

The best

Chinese: 最好的 (adjective)

最好

and if you want to write it out yourself, I suggest coping and paste it into a word document and enlarging the size to a much bigger font so you can see the details and strokes and have an easier time trying to copy it.

the best = 最好

Since there's no "THE" in Chinese, "best" & "The best" would be the same: 最好的, "zui hao de".

You simply DO NOT know CHINESE or haven't learned enough CHINESE if you don't answer with 的 at the end. Online & non-Chinese translators tend to be wrong. Foreigners mostly used online translators which tend to be wrong most of the time.