I'm a beginner in french. My method to learn a language is reading.
Which one of those books are easier to read (I mean, which one has more commum words):
À la recherce du temps perdu;
le médecin malgré lui;
Double assassinat dans la rue Morgue
(If you don't know the books above, they are super easy to find in PDF. I think a simple look is enough to answer)
You have my gratitude even for trying!
The first and the last ones are very difficult and require a native-like level. Besides, Proust is kind of heavy, so I definitely not recommend it for studying French.
In general I suggest you to take a police story, generally it's easy and motivating cuz you always wanna know what happens next. Or some romance like Anna Gavalda. Or if you are a complete beginner take an adaptation or children's book. Or a magazine.
I would recommend something more recent, modern.