I have a raised brown flat bump on my right hand its small like a centimeter big and i just want to know if its skin cancer or not.

Probably not: At age 20 it is statistically very unlikely to be cancer. A mole is brown but 1 cm diameter,is a bit large so it is best to have a doctor check it. You may just be reassured or have it removed either for diagnostic or cosmetic reason.It would be guesswork to give an accurate diagnosis online.Take care.

See your derm: Any new or changing skin lesion should be brought to the attention of your dermatologist. If they are suspicious of the lesion, a simple skin biopsy is performed to obtain a diagnosis. And also remember to limit your exposure to UV radiation. Wear sunscreen with an SPF of at least 30 and try to cover up as much as possible.