Surfing Waves

Hello, I'm getting a new board. It's either a 7ft-21.25-2.75 or 6'8"-21.75-2.75 but I don't know which size is better. I'm 15 am 5'7" and weigh around 135. I will be riding 3-6' waves mostly. I am beginer/intermediate Also do you think I need a traction pad?

What are you currently on? Define "beginner/intermediate".

If you're really edging towards intermediate then the 6'8 will be more than enough (too much?), but if you're a beginner, then go with as much volume as you can get hold of and get the 7'.

By that I meant I am entering intermediate as I can trim on my longboard, do bottom turns, and nicely ride a wave

In which case, I'd go with the 6'8

Agree, go with the 6'8. At your level and size, that should work out fine. Don't think you necessarily need a traction pad, thinking at 5'7 you're going to probably be shuffling back and forth a little bit when up and riding. However I personally like traction pads, as I can tell right away if my foot is in the correct position and feel its gives a little added padding/protection from my foot when duck diving.

6'8, when you get better it will be your step up for big waves. At 135lbs you could go smaller, but good that you are going down incrementally