Do you get stronger when you get older? my brother is stronger than me but i am more muscular and hes a bit skinny and we also close in height he is 6 ft and i am 5'10.5?

With regular exercise muscles become more efficient even without increase in muscle mass. Your brother's muscles are more "experienced" and more efficient, even if you have larger muscle mass. For healthy diet: http://www.choosemyplate.gov/., exercise 30 minutes/day, drink enough water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs.