Hello, I am new to horseback riding. I went to a local store to find the right pants but got confused. My question is lets say a person wears an extra large in bottoms what would be good fitting for these pants. I saw (L) and (R) listed whats the difference? Also what is a 34R would that be like a size number like 11,13 or 14 or something in regular. Please help me out : ) thanks!