Slow down there cowboy.
I have sooo many things I can say about these but I will make this short.
First off on the list, get a good sketchbook from like Blick's or from Michaels. This will give you a better space for the different kinds of pencils you use.
This brings me to the next part, I know that pencils don't really matter that much unless you were me. In my opinion I like to start off with a 3h-5h pencil for the sketch and increase (or decrease) to 1b and 2b pencils. This would give you harder and softer tools to get the value you want on your art.
Next, get your proportions as best as possible and take your time to make the hands, eyes, and mouth as perfect as you possibly can. This will come in handy (Pun intended) for when you get to the shading. This gives you a better understanding of how the light will affect the different regions of the face and body.
After that, don't start your drawing with really dark lines so you can shade and so you can erase if necessary. On some occasions you can start with dark lines and work your way out but that is for another thing. If you fuck up you can easily erase it and make some fixes.
Shading is later, blah blah blah.
Here are some reference images to help you with proportions and get you to make those crusty hands and weird looking face parts out of the way haha
WARNING: BIG IMAGES