How do I reply to "반갑습니다" I am using a language exchange app and someone said hangabnida which I know means "Nice to meet you", how should I reply?

What Korean verb politeness level do Koreans use on the internet? For example on a forum to strangers, or on a Youtube comment, which form do they use? habnida/yo/ect.. I know korean learners probably stick to the polite form on the internet, but if korean natives are chatting to each other or commenting on something (strangers) then I don't know. The reason I ask this question is because I play League of Legends and I'm trying to figure out what form they use in the chat.

How to say "Let's Wait" in korean? Korean learner here, was wondering how do say the phrase "Let's" in a korean sentence, I know wait = 기다리다 Is 기다래요 보자 Correct? thanks.