Some Little Help Please

I don’t even know on how should I write my fics. I have a clear idea on what I really want to write about but I just simply don’t know how start my stories, especially when it comes to grammar and sentence structuring. I could probably go to fimfiction to ask this question but I wanted to know if you guys could give some ideas as well.

What are your favorite type of genres and structures?

Depends on what you’re writing. Is it dark? Is it sad? Is it happy? Does it make you think?
 
Sentence structure will depend on how you like to write. Sometimes you pick up on stuff from other writers and don’t even realize it.
 
You could try looking up stuff on grammar. I don’t really have good grammar.

@monus783  
I have only two real pieces of advice:
 
First: Whatever you want to write start writing it goddamn now. I’m serious. I don’t care how bad you think it is, or how little of an idea you have of what you’re doing, start writing. Even if its just the scene you want with no other context added, start writing it.
 
The only way to get good at something is practice, practice and then practice some more. Try to get at least 1,000 words written a day.
 
Second: When you aren’t writing, read. Read all the books, and then rip them off shamelessly in your practice writing. This teaches you structure and grammar better than any guide.
 
It can be anything you want as well, books, fanfics, even just writing out a tv show as if it were a novel.
 
There is no magic recipe for writing, there is only thankless toil for hours and days that you undertake for the chance of having your words mean something to another human. You will make absolute crap, but do not let that discourage you. Every writer produces crap from time to time, and it is nothing to be ashamed of.