French here.
1. It's considered rude to speak a foreign language to a local right off the bat. Might get away with it in Paris but in most smaller cities, people do not speak anything else than French.
2. Saying hello to people randomly on street, you're not going to get a reply because people think you're weird. People don't say "HELLO, HOW U DOING" to everyone like in USA, in a fake ass manner. We usually say "Bonjour/Bonsoir" in a polite manner when entering a store or something, but not to random people lmao.
And besides major city like Paris and a couple others, where people are in stress mode, people are usually nice.
Just nice in a "European manner" which is usually more reserved than Anglophone areas.
And if you think France is reserved/standoffish, try going to Northern Europe, where nobody talks to each other and even being close to each other in public is uncomfortable.