I'd like to recommend creating a account so me or other members can assist you, as guest have limitations in replying here and if we need further Information to communicate with you.
I'll provide a link to register, please come back to your post so we can further assist you . Thank you
It's a Chinese device, you can't just change everything to English, nor can you use Google or flash any non-Chinese firmware. There's nothing you can really do, sorry
Many apps use the default language in the phone, but some have the language hard-wired into the app. so as Galactic Zoo said, there's nothing you can do, but install the English-language version of the app (if there is one). That will require uninstalling the one in there. If it's a system app, that will require rooting.