Everyone has been asking but there really aren't any words that do justice for a city like Paris... all I can say is it's gorgeous and I love it.
Some things I noticed as a first time visitor:
Other than being effortlessly fashionable, the French are all about: bread, cheese, desserts, coffee and wine. It's interesting. Parisians walk super fast like, I-have-a-really-hard time-keeping-up fast but when it comes to eating they're super slow. Not in a bad way at all. I think it shows food is a huge part of their culture, they really enjoy it and the people they spend it with. Once you sit down you can stay as long as you like. Because of this tables are turned much slower if even turned at all so making reservations is highly recommended. In the US dinner is usually between 5 to 7pm. In France, 7pm is considered very early so make sure to check business hours on Google Maps beforehand. There were several times we showed up to restaurants assuming they were open and they weren't. We learned real quick haha. And sometimes we couldn't even get into a restaurant because it was completely booked. To summarize, making reservations in advance is highly recommended, especially for le week-end. You can use their version of Yelp, La Fourchette (The Fork) app.
Like other euro cities, cafe culture is strong in Paris. Boulangeries and pâtisseries exist pretty much on every corner which makes it difficult to choose. During lunch hours it's normal to see locals walking and eating at the same time, usually a baguette sandwich of some sort eaten straight out the paper bag. My favorite is watching the locals walk home with a baguette or two sticking out of their work bags or purses. Makes me smile every time.
Parks are very relevant and used by locals often, especially on the weekends. The bigger gardens like the Tuilleries and Luxemborg are tourist hotspots but it's just as normal to see the locals bringing their children, dogs and catching up with friends and family. Some are working out, some read books by the fountain, others take naps (literally some of the chairs are designed to lean back so cat naps are a-okay). Parks are a lifestyle here and I love that.
For those of you wondering, I don't speak any french. Non, other than the basics like bonjour, bonsoir, merci, au revoir, s'il vous plaît, etc. I have been learning on my own using an app called Duolingo and Coffee Break French podcasts which are on Spotify. It wasn't much but I found it helpful to have a little bit of knowledge and an idea for pronunciation. Also you hear french 95% of the time, so I learned some new words and phrases, yay! Hopefully once I move I learn a lot more with the help of french friends. Side note: if you are french and in Paris, let's be friends. Like for reals.