How do i avoid fighting without looking like a ******?

Im one of the biggest people at my school( and im black,and from south-centrla ),but i dont like to fight,i like to avoid fighting until i get older. I have alot of homies and they expect me to know how to fight,etc. And if i turn down a fight i will look like a ****** and i wont have friends anymore,so can you help me? Give me some excuses or something?