He was too kind that I fell for him

Yoo, what a cheesy title, huh? Well anyways, I'm going to start off that I never talked to him in real life. Just through Facebook, but I have seen him in real life but we never spare glances at each other.
He's my senpai―already graduated. I have liked him ever since I first laid my eyes on him during a sport's festival at school. We played the same sport...well, board game (yeah, we're nerds.) A teacher in charge of my grade was training me; competing against her. I failed, ofc. Her old student came and just stood there. Felt no reason to notice him, and I just continued the game. The teacher made him play against me for one round. I looked up at him, and he was staring right back at me. Very dramtic wooshes, and to add that the sunlight was behind him. I started liking him since then. He's my first love.
During the summer of 2016, I chatted him. Wasn't weird cause my best friend became friends with him that summer, plus it was a dare. He didn't respond at first and just sent, "." Annoying as heck tbh. I kept getting dared to do something to him COINCIDENTALLY. A few dares later, he started talking to me. We chatted for less than 3 months almost everyday. Some memorable conversations were that: I was afraid I wouldn't get in the star section anymore in which he encouraged me that I will be (he's smart af), I had to go home all alone at night and he wanted me to contact someone to fetch me instead but gave up and just told me to contact him when I get home safely, our love for bacon turned into capslock party saying "BACON WOOOOO," and many more.
I coincidentally saw him at a store. I saw him, he most likely saw me cause he was behind me. I was sitting down to look at pens, he was behind me standing up, also looking at pens. But other than that. I was completely ｉｇｎｏｒｅｄ．The next school year came. We saw each other. I glanced at him, but he didn't. He ignored me again. We never chatted during that year.
I confessed to him via chat after that school year. He said, "Thanks, I think I already knew." The best reply he could have given. Forgot about him that summer then the next school year came.
I found out that he's actually never online. But during that summer...he was always online though? He was always able to reply back?
Note that we never chatted again.
This was his last year. And this year was very...it was such a burden on my shoulders. We'd still pass by each other, but this time, my friend and him were closer now. They'd hug when they saw each other. Every time. I had another friend with us. We were a trio of best friends. I think my friend got the clue when they'd hug, and drags me away from them. I can't help but feel that...he's doing it on purpose. One time, we were on a three day streak going to this fast food―us the trio. He had a huge group with him, and they'd sit near us. First day, he was a little far, so phew on me. Second day, I could see his back. I begged God that he wouldn't look back. But nope, he did. He saw that we were trying to forge a signature cause my friend will be dead if she didn't have one. The one close to him asked him to sign it. He refused, but continued to look back at us. He was right in front of me. I was looking anywhere but him and it so obvious, but I couldn't stop. It felt like he was taunting me.
A few instances like that happend again. Everytime, I was afraid to look at him. The same feeling of taunt was there. But when we were at school one time, we were about to go the same path, we both headed for opposite directions. Another time, during that year's sport's festival, he came to my group of friends to compete with them. I was just there. He was looking at volleyball match before WITH HIS FRIENDS, but he decided to stay with us. He still cheered for his team from afar, but he stayed at our table. And I felt so suffocated and taunted.
I decided I wasn't going to get riled up about this and I would raise my head up instead. I raised my head up when he hugged my best friend tightly. I saw his head rest in my best friend's shoulder as I saw my friend's back. I put on a straight face.
He graduated now. I NEED to get over him. Although I felt what I said above, I am super thankful of him. Without him, I would have never met my friends...never stayed in the star section. I was determined to be his level that I did my best in academics and be able to stay in the star section where all my great friends are. He was just so kind that summer of 2016. I really really like him. He isn't even my type. His likes are a total turn off for me. He has a cute face, but only sometimes. I sometimes think he's ugly haha. So irdk why I yearn for him. I want to move on. How?

I want to talk to him irl, but I'm probably already bothersome for him.

He's probably bi too...or even gay, but I just want to be friends at least. (Also, I'd def support)

(sorry for really long story. I felt that if i explained, you guys would understand it more)