If a boy clearly remembers a girl's birthday, constellation and age, what does it mean?

If a boy clearly remembers a girl's birthday, constellation, age or other things, I think the boy is at least interested in this girl. Whether he likes him or has a crush on this girl, he will want to remember everything about this girl. If this girl is not important to her, he doesn't have to bother to remember it, does he? Sometimes, if you really meet such a boy, it's quite intentional. You can try to contact, contact, may have unexpected effects. Because we are girls, it should be appropriate for you to pay the bill if a boy does it.