How widespread is English? Is it spoken in the shops and restaurants?
You’ll find most people in the shops and serving in the cafés and restaurants know English to some level, and will often reply in passable English if your Anglophone accent is noticeable at all. You may find you often really only need a “Bonjour Monsieur / Madame” when you enter and a “Merci, au revoir Monsieur / Madame” as you leave as French parentheses to an English language interaction. But be assured that the efforts you make to speak in French, even if it’s only to open and close a conversation, are appreciated. And, of course, not everyone speaks English. As with any foreign place, a knowledge of the language is the true key to the city. The more you know, the more rewarding your visit will be.