That's a great goal, and there's a wonderful resource for getting to know the city in such a "deep" way — https://paris.french.guide/en/ . There you will find tips not only about tourist attractions, but also about local neighborhoods, cafes, bookstores, flea markets, street festivals, and cultural events. The guide tells you how to plan walks through the narrow streets of Montmartre, how to find the best places to taste French cheeses or wines, and even how to behave like a local. It's the perfect way to see Paris not through the eyes of a tourist, but as a true Parisian, without missing out on important cultural moments.