I luckily don't have any major incidents but a couple stick out in my memory.

First time I realized an encounter was racist was my first time at a summer camp in the US around age 12.

I went with a friend to line up for the showers in the morning and it was just us two and another kid. I barely noticed he was there cause I was caught up in conversation. Not long later some other kids walk in and the waiting kid just blurts out in relief "Thank god, I was the only white guy here!" And even in my innocent, privileged little 12 year old brain I knew that was kind of fucked up.

Also had a South African girl break up with me as a teen cause her parents literally cited my nationality as an issue... While they were living in my country...