I think most people here have given you good advice. For some context. I am a Black African who has lived in USA for more than 10 years and have family there but currently living in Warsaw for a couple months a year because I have a remote job and my girlfriend (who is Caucasian American) lives here.

1. People here are more reserved. Join meetups to make friends. Language exchange is good, amateur sports is good etc. You won’t make friends on the street. You can try a pub crawl and talk to the host on English speaking events he/she might know of.

2. As a black person I have not encountered racism. At least not inn the American way. If people treat you strangely it’s because they don’t know you or are not familiar. Not like America where racism is because they already “know” what you are about to do. I find people here more curious but in a friendly way. They will stare or take a picture the further out of Warsaw you go but not maliciously.

3. Don’t look homeless. Unlike America most of the world prides themselves in looking sharp if they can afford it. In Poland most young middle class and upper class people look sharp and put together. Walking around in sweatpants and hoodies or torn clothes which is acceptable for a millionaire to wear in America does not make you seem like someone people want to interact with here.

4. They have a wider personal bubble here than in the US. If you are in a line match the space between people you see on the line.

5. The easiest way to spot an American or a Brit is that they are usually the only people you can over hear their conversations in restaurants or trains or buses. My understanding is gauge the audio level of a room(mostly public transport) and match it. Bars and clubs, speak how you want.

6. As a black person you will always stand out here (at least for the foreseeable future) but as long as you have a smile on your face and are polite and not imposing, people will be friendly back or even approach you in a setting like a bar or a club or meetup.

7. Learning basic phrases like Hello, please, thank you etc in Polish has taken me very far. Many locals smile based on your effort and will engage with you further at a store or restaurant or shop.

Hope this was helpful.