Hi,
I don't really know how to help you, everything in the game is pretty much self-explanatory, or you can try different options yourself to discover some actions.
Regarding the "her arousal" part, that 'Z' icon represents her wakefulness (she wakes up if Z is full), if you want to have sex with her you need to first make her cum at least once.
It doesn't matter if you're Chinese or American, all translations are delivered by people for people, dev has nothing to say in this matter, you can only be thankful to fellow Chinese players that volunteered to manually translate the game by themselves, so that you can play in your native language.
Cheat codes are available on our Discord server or you can look for them in various forums over the internet.
Hope this helps,
Cheers