14 year old guy, trying to build muscle. Help?

I'm a 14 year old boy. 140 pounds and 6'0". Tall but VERY skinny. I'm trying to build more muscle in general, especially around my stomach, chest and biceps. My dad has a workout bench (a WeiderPro 290 W). I recently started bench pressing and curling on it. Can anyone give me an idea what I should do, or even come up with a regimen for me? Thank you.