Have you thought about perhaps taking an English course of some sort? I'm sure there's a few free online courses you could study. I mean, even starting from the opening line, there's clear issues happening.
"Why the fuck, that oldman often picks me for this kind of task?" is wrong on a few different levels. It should look something like "Why the fuck does that old man always pick me for these jobs?". Doesn't that roll off the tongue a little better? Even better, you can add some slang to it. "Why is that geezer always picking me for these fuckin' jobs?" What exactly is there a comma after 'fuck'? You're not putting an emphasis or separating fuck from anything, so the comma is unnecessary. Who is Oldman? In this context it's not a name, but describing someone by their age. This shouldn't be capitalized.
"I want to punch your dad in his face" is pointless here. Obviously if she's going to hit someone, she's going to aim for the face, so why included the unnecessary detail? All she has to say is "I wanna deck that old man/geezer/grandpa/etc," or "I wanna clock your dad,".
"He thinks he can order you. Just because you are his daughter, THAT OLDMAN!" This is a little better, but still quite unnecessary. "He thinks he can order you around just because you're his daughter. That damn geezer." People don't typically say 'you are' in everyday speech. Contractions are your friend. "I've" instead of "I have", "You'd" instead of "You would", etc.
"Hey, Don't listen to that bitch. He had high hopes for you, trust me." Angel uses 'Hey' to get her attention, and thus a statement. This is one topic, so instead of a comma, use a period. Then there's the 'he had'. Is the 'oldman' dead, has he disowned this girl? Why is Angel speaking in past-tense? Assuming he's still alive, it should go something like "Hey. Don't listen to that bitch. He has high hopes for you, trust me."
"WHO ARE YOU CALLING A BITCH YOU DICK LUST DEVIL." Let your render do the speaking here. Devil is obviously yelling in the render, so there's no need to write that in all caps - or use a period. What's a 'dick lust devil'? She's calling her a name, so after bitch, use a comma to put emphasis on it. "Who are you calling a bitch, you dick-crazy devil?!"
That's just the first few lines of the VN. It may come off harsh even I'm being constructive, but you need quite a lot of work. Have you thought about bringing on a native English speaker for the project? I'm sure there's someone or someone(s) that would volunteer their time to help translate/clean up your writing.
