The proper tool for removing the adjustable cup (lh side) is a hook spanner such as the Sugino BB tool. There is a Park tool that might be the same functional thing and they're cheaper. I've never used a Park.
So, you use the hook spanner to remove the ring and then the adjustable cup should be easy to unscrew, maybe by hand. If you don't care about the old BB, you could use a hammer and punch to remove the ring. On the left, both the ring and cup are normal rh thread.
Then, you've got the fixed cup on the RHS which, being a French bike, is probably rh thread also.Depending on design, you may need an odd tool to remove it. Or, you might be able to unscrew it by clamping the fixed cup in a bench vise with good jaws. Rotate the bike to unscrew. Or, you could try the famous Sheldon Brown removal method. Many people have luck with that.
Curious, what BB and crank are you going to install?