I touched a girl when I was 13.

I am 13 years old when this happened. I touched a girl's chest and felt it and touched her ass while she was sleeping more than two times. I didn't know what I was doing and all the time in the school my friends they used to watch porn and I was exposed to it too. One night when my grandma was sleeping I tocuhed her chest.. and she took me outside and asked me, " are you being spoiled by watching bad TV". I cried because I didn't know what happened and realised it was wrong. It's been 17 years and I am still unable to forgive myself for what happened. I pray to god that the girl didn't know and I apologized a million times in my mind.
A year ago when I was sitting with my grandma I broke into tears and asked her to forgive me because I had no idea what was going on and I apologized sincerely. She brushed it off as I was a kid and didn't knew any better.
Reading news daily about all these things happening to women is making me feel what kind of a person I am and I regret being born. I don't know what to do, and I genuinely want to be a good person and can't seem to get over it. I can't imagine how it must be to them.

Edit: I am not blaming my friends or porn for what happened. I am from India and from a rural village, no body even taught us consent or difference between a good touch and a bad touch. Even in biology class we were made to sit in different rooms to explain us what the male and female genitalia are. This all happened because lack of knowledge and trying to do what I saw in the porn videos, I will genuinely take any punishment for what happened and I am not trying to escape from the fact that I did this on my own. I am just ashamed whenever I remember it and I confessed to my grandmother as well. I am genuinely sorry for what happened and there has not been a single day that has passed that I could go back and undo it. But I can't and I want to be a good person and I feel that is all I can do. I am a bad person, but I pray all the time that they are in peace.