I am 17, my voice hasn't broke yet, i have a small penis, little hair under my armpits, i am 174cm, all my friends look bigger than me what can i do ?

Need more info: Some people mature at different rates and a lot depends on genetics. To allay your anxiety consult with an endocrinologist that your family physician can recommend. He/she may order some simple blood tests and together with a physical exam be able to best answer your questions.

See a pediatric : Endocrinologist, but first see your primary physician for a physical exam ; referral. The most common reason is constitutional delay of puberty, meaning it'll happen late ; you'll be tall, but it's worth knowing that you needn't worry if that's what it is. Ask your parents for a 3-generation family history ; if your ancestors were of north european origins.