I want to start a relationship with a guy I like but I don't know if he likes me. He is friendly but I am shy. I want to get closer to him. How should I act around him to get emotionally close?
You state that you are 11 years old.
There are different stages of life, and they are for different things. A "relationship" is basically for settling down and having children. Are you ready for that? Or do you want to live for a while first?
Having a boyfriend is a fun way of learning how to have relationships later on. Girls and boys form a group, and pair off for a while. They break up, learn from the turmoil, find another special friend. This can and should happen several times.
Despite what you see on TV and what you see other kids do, having a boyfriend is not good for a girl of 11. It actually gets in the way of learning stuff you are supposed to learn about, like how to get on with boys. What you need, and what is really fun and enjoyable, is to have friends. Some of these friends will be boys, some girls. Some will be closer than others. It is perfectly fine for you to have this boy as your friend, even as your best friend. You can do things together, talk about stuff that interests you both. But don't make it "I am yours and you are mine until death do us part." That's nonsense for someone who needs to learn through experience about how to be friendly to all sorts of people, not just a few.
I have had clients who are about 30 to 35 years old. A lady may love her husband and kids, and has no intention of breaking up her marriage. All the same, she has gone and had an affair. The husband has found out, and is terribly hurt. She loves him, and hurting him hurts her. But she has done it. Every time I see this pattern, I find out that they teamed up very young, maybe 15 or 16 years of age, and have had no other partners, ever. Kids, boring job, bills to be paid...life can be a chore for people. Then, some look for something to blame. If she picks on the marriage as the supposed cause of her dissatisfaction, she is ripe to be seduced by some man looking for easy pickings. She missed out on the freedom of being irresponsible and unattached when young -- so she became irresponsible when she "should know better."
So, it's OK to like this boy. It's OK for him to like you. Be friends. But it's not forever-love. Have fun, learn about life.
You may find that if you have this attitude, then the shyness will go. You don't need to judge yourself, or worry about the impression you are making, if you are only aiming at having a fun time.
So, have a good life, my dear.