Okay first of all, Grammer, is it important in English?
It is both yes and no, why?

Okay, I have been to a lot of country in the world, Switzerland, Copenhagen, Denmark, US, etc, and I all of the citizen around there seems okay when they hear wrong grammer as long as you say the right thing. For example : "I want to eat" is the perfect grammer but if you say "I want to eating" with wrong grammer, they won't laugh or teach you the correct grammer, they just simply answer your question or response to it.

But it is important while your job is reservation that type a lot of email to other. Or maybe a writer, yes it is important.

What is Vocabulary, it is simply "kosa kata". The more you know about words in English, the easier it will get.

Now I will give you some important words and phrase that maybe you haven't know yet : 
1. In addition : Selebih nya tapi masi satu tipe
e.g : John likes to write a novel. In addition, He also like to write a book
2. On the other hand : di lain sisi
e.g : John likes to eat. On the other hand, Susan hate it
3. Convenient : cocok, nyaman, pas
e.g : A big parking lot makes going to shopping mall convenient
4. Close : Bisa arti nya tutup, bisa arti nya dekat jika ditambahkan dengan by
e.g : John's house is close by his girlfriend's house.

And pronounciation is "pengucapan". So how you say it, like for example, you need to know how to read a single letter, like come, roughly come will be pronounce as "kam", not CO-ME. University = "yuniversiti". 

I can help you with : 
1. some english lesson through online chat
2. Translating your document in English 
3. Help you to check your English in a couple document (e.g if you write an essay, i can check on it)
4. Help you make "skripsi" in English of course. (it is helping you to understand and translating it in english, not make it for you -_-). I was graduated and went to college in Switzerland and English bases college, so I understand about "skripsi" and how to write it.
5. Answering some question in english (e.g. spoiler, if you want to work at gojek, there is some test in english, i can help you with it) 
6. etc, Maybe you have your own problem that need to be solve in English

Above all, of course there is price for everything, you can chat me on WA to be more precise.
Maybe you will think that this is a scam or you think I just want to help you for free. 
Okay its not a scam, you can chat me if you want, not that I order you to chat me and if it for free I cant keep helping you or other people that need it, got it?