Is it normal to check girls out?
Mostly.Normal for most people
Yes, it’s normal to notice people you find attractive. A quick glance is different from staring or making someone feel watched, so keep it respectful.
People naturally notice who they find attractive, whether or not they’re single or looking to date. A brief look is pretty ordinary; most people do it now and then.
The line is how you handle it. Repeatedly staring, making comments, or checking someone out after they seem uncomfortable can feel intrusive. If you mean girls who are underage, don’t sexualize or pursue them; keep your attention to adults.