For beginners I recommend starting with either charcoal or graphite.
Graphite is for the people who don’t mind taking their time. Graphite is smooth and easy to get that desired sharpness and detail. Graphite blends very well with tools like a blending stump or my favorite, a q-tip. Pencils are very easy to transport and easy to hold without getting messy.
Charcoal comes in different forms like, sticks, pencils, chunks, vine and compressed charcoal. I usually would recommend charcoal to people who like drawing fast large drawings. Charcoal is very unpopular because it can get very messy. But you are able to achieve that blackest black matte darkness and it won’t turn shiny like the graphite.Be careful with your work because charcoal smudge very easily. You whites have trouble staying white unless you over them up with artist tape.
In conclusion, I suggest, use both and experiment. Use the pencil for the detail and use the charcoal to value out your drawing. Charcoal and graphite actually don’t work well on top of each other but if you know what you’re doing, you can make it work.