Rum is a distilled beverage made from fermented molasses "beer". If you're in the US it is illegal to distill without a ATF permit. Other than that, you just need to ferment then distill.
We avoid discussing distillation here for several reasons. First, it is illegal in most countries where our members live. Second, it does not pertain to homebrewing beer, wine, cider, or mead. Please visit another site to ask your questions.