In English, when we meet new people, we can use different greetings, based on who we're talking to, e.g
Formal: "Good morning, afternoon, or evening."
Informal: "Hey!" or "Hello!"
Bonus: Regional greetings are common, but can be confusing or insulting to foreigners, e.g South African English speakers sometimes use "Howzit!" or "Hola!" (The H in Hola is sometimes pronounced like a W, giving you something sounding like "W-h-ola!") Not to be confused with Spanish, where the H is silent.
It may seem overly familiar, but can be a good way to immerse yourself in the local vernacular.