You can't. Gtranslate is absolute rubbish for Japanese and Korean, in my experience. It only really works on simple sentences, converted to English.
It does not generate formality levels correctly or consistently at all, so if you translate multiple sentences it can go from non-formal and non-polite to very formal and polite.
English is more or less a universal language, and esperanto will never achieve anything other than being a toy language for nerds. It's neat, but that's all it is. You would be better served learning Mandarin, English, Spanish, or German.
It does not generate formality levels correctly or consistently at all, so if you translate multiple sentences it can go from non-formal and non-polite to very formal and polite.
English is more or less a universal language, and esperanto will never achieve anything other than being a toy language for nerds. It's neat, but that's all it is. You would be better served learning Mandarin, English, Spanish, or German.