Okay, so you're in too much of a hurry to waste time exploring. You just want the guts of it. The magic pill that I suggest.
Very well, then.
There are two ways to go about learning a language. You either learn it, or you pick it up.
Guess which way is better?
All 7,000,000,000 of us mastered our mother tongue by picking it up. As babies. By the time that we were a couple of years old.
At school we tried to learn a language. For several years in many cases. And for most of us that did not go well.
You see where this is going?
Now go and google Stephen Krashen. What are you waiting for? Spend 10 minutes or so of your valuable time listening to him speak on Youtube. Doesn't matter which of his talks you listen to; it's all excellent.
He's still alive, so hurry!