Here’s my personal advice, AKA the advice I’ve given my brothers: You can approach anyone. The important part is knowing when to back off. Approach gently, where she can see you coming, smile and introduce yourself, and watch for signs that she’s uncomfortable. If she seems to give short answers, isn’t looking at you, isn’t engaging, etc. back off immediately and don’t approach again.
just to add on: laughing could possibly be a sign of being uncomfortable. women are taught to deescalate situations with men and to not offend or piss them off and that’s often how we do it. ik it sounds a bit confusing, but it’ll be pretty clear if she’s uncomfortable by her body language