I would say introvert. While I don't struggle to interact with people, I absolutely need my alone time to recharge and chill and feel less stressed. I've just done 6 weeks in almost constant company with 7 other people and I'm absolutely exhausted.
When meeting someone I usually notice how they look, what kind of clothes they wear, if they have dark circles under their eyes, eye colour, etc. You can usually learn a lot about a person and their interests/personality by the way they look and It can always help make a good conversation better by complimenting something they’re wearing or their style