Safest bet is to just mirror how the other person talks. Generally speaking on something like HelloTalk you’ll want to start off with desu/masu and then drop it if the other person does/when you get more friendly with each other. Some Japanese people have a habit of talking more casually to foreigners than they would to other Japanese people since foreigners are viewed as more friendly.
As far as 僕 vs 俺 goes, there are few wrong answers. Do what you like. I know adult men who use 俺 and adult men who use 僕. I know adult men who switch between the two of them depending on the situation and the tone of what they’re saying. At a certain point it’s more about vibes than there necessarily being a “right” answer
Hi there, I’ve worked professionally in Japan for three years, I can provide you with my experience. I am begging beginner learners to stop cramming formalities and です・ます into every conversation. It is so stiff and formal. If you’re talking to strangers, it’s probably because you want to get closer to them right? A little formality is fine enough to show respect or whatever, but don’t completely cut them off.
In Genki 1, one of the first introductions you learn is : お元気ですか？はい、おかげさまです！This is like crazy over the top, almost sarcastic lol. My best advice is to listen to the other speaker and match their level.
A nice middle ground is half and half:
日曜日には予定がありませんので、会いましょう。X
日曜日には予定がないから、会いましょう。O
You’re still being “polite” but it’s not so stiff. And lastly, if you’re wanting to be more casual with someone and they’re locked into です・ます feel free to tell them to stop. It’s a compliment in most cases. You can just say: 敬語じゃなくてもいいよ
The setting plays a big role too. At a bar, I will not use formal Japanese at all when talking to strangers. If I’m asking questions or interacting with people on the street, it’s usually a 70/30 mix. Sure, some people on this site are going to tell you you’re being a rude gaijin and you need to always follow the textbook exactly, but that’s not how language works. If you’re using this language because you want to make friends, then talk in a way that friends do. If people think you’re being stuck up because you didn’t show them enough respect, do you really want to be friends with them anyways?
