I like younger girls more.
What is your reason for liking younger girls?
The short answer is - it's easier to talk to them.
It's not right to like girls under the age of consent. You should like girls that are more closer to your age.
You don't understand, older girls are out of my league.
Older girls are not out of your league, you may just lack confidence when it comes to talking with them. Try to have the same confidence you have talking to younger girls when you talk to girls your age.