How do you even get tested these days? I got tested when I was 13 in a classroom setting many moons ago (not in the U.S.), and no one in the class knew it was

How do you even get tested these days? I got tested when I was 13 in a classroom setting many moons ago (not in the U.S.), and no one in the class knew it was IQ test. I moved to the U.S. shortly afterward and I don't recall being tested.