Lived in/around dc for 20 years heres my take:

Good call on the museums. Best stuff we have. Dc has a strong black american culture which can be seen in the music, cuisine and every aspect of the living city. (I recommend going to church at an american episcopal service on sunday its jaw dropping energy and tbh no where on earth has a religious service experience like black america does with its christian services.) a lot of our famous musical artists grew up in these churches

The political vibe is very liberal, with a strong gay prescence and quite tolerant and welcoming to outsiders as yourselves. weather is notoriously unpredictable, check your apps couple days in advance. Dont do the aquariums theyre lower tier. The natural history museum will do well instead. China town sucks. Kennedy center is cool and breathtaking if you like music of any kind. National zoo is ok, but lots of walking. The city is very spread out, plan your routes carefully or be prepared to to pay out the ass for your ubers.

You dont need cash, and you cand find sim sellers on every corner.

Btw just be prepared to walk everywhere. Honestly go buy three folding razor scooters when you arrive and then donate them to a homeless person or charity when you leave. See a walmart or costco if you havent, theyre kind of the most american thing ever. Huge pakistani community in arlington/northern virginia u could high five someone you already know. Food: No one serves an exclusively wine/pork menu thats not a thing, and if youre nervous about the menu ask your server about it, theyre likely well educated and well travelled. We have a lot of ethiopians and cenral american imigrants these days and they brought their glorious food. Try it at least.

Good luck and believe me when i say this subreddit is not the place for you to try and understand what dcs really like lmao