Aug travel to Quebec City

Hi everyone! My wife and I are traveling to Quebec City August 1st and are in search of some advice.

1. What are sights, activities, restaurants, etc that are a must in and around Quebec City?
2. Is renting a car advised/needed?
3. Any advice on places to stay? Are there any areas that should be avoided when searching for hotels? I’m also considering an Air BnB, is that a good choice or not? Thanks in advance everyone!