I'm not a native Russian speaker, so sorry if that's who you're looking to answer this, but спорт is a noun, спортивный is an adjective. For instance you'd say спортивный зал (gym - lit. "sporting hall"), but спорт зал is incorrect. Футбол is a спорт. Russian adjectives are easy to identify because they end in M: -ый/-ий N: -ее/-ое F: -ая/-яя
Hope that helps!
if not not mistaken, the adjective form of "sport" is "sporting", right? So, "спорт" is a noun meaning "sport", whereas "спортивный" is an adjective meaning "sporting". For instance, "I've been playing sports all my life, but I don't have any great sporting achievements" would be "я занимаюсь спортом всю свою жизнь, но никаких больших спортивных достижений у меня нет".