I studied at an international school that followed the French curriculum, and I'm studying Law at a university in France, so feel free to ask any questions.
The baccalaureate is very difficult, however it's good in the sense that it provides you with a broad education. It's not like A Levels where you pick 3/4 subjects. You have to pick a 'stream', which could be science,literature or economic and social sciences. But for example, even if you pick the science stream, you still have to take non-science subjects- it's just that they make up a lesser proportion of your overall score out of 20. Philosophy is also compulsory across all the streams.
Regarding university, I'd recommend you to study Law at a UK university, especially if you wish to return there to practice. The quality is probably better there. There are some good universities for Law here also, such as Panthéon Assas, Paris-Sud..