I'm going to let you in on a little secret Skeleton.
Not particularly about girls, but about humans.
We, almost without exception, across the wide world, want to connect with someone else. Not in the "let's have a romantic relationship" way, or in the "I'm too shy to start a conversation" way.
But almost every person enjoys a sincere, regardless of how brief, human interaction with another.
That my dear, is your practice ground.
Every encounter we have with another human is a mini-relationship. Even if it's just 2 people in their cars, and one waves to the other to pull into traffic in front of them, especially if other waves back thanks. Don't ever underestimate the impact of such a small gesture of kindness. That's important enough to repeat.
Don't ever underestimate the impact of even the smallest gesture of kindness.
Don't EVER worry about possible reactions when you give another person a sincere compliment. Even if you receive a strange look in response, you have done bridge building, if the compliment was sincere. It doesn't even have to be about the other persons appearance. A compliment can be about what the person in front or behind you is buying, or an interested question about it.
Every friendship starts with a little tiny reaching out to each other.
Corny as it sounds, if you're the one that reaches out, even a little, the other person reaches back.