All praise be to Allaah, who has guided you to Islam, and we ask Allaah to give you the strength and courage to be steadfast in following His guidance. It is the greatest blessing He has bestowed upon you, and it is incumbent upon you to express and show thanks for this blessing, by worshipping and obeying Him.
As for your question, wearing hijaab is a mandatory obligation which cannot be neglected. If you cannot find a place in France that will allow you to work while wearing hijaab, then you must strive to move to a country you can wear the hijaab while working, as you have indicated. It is not permissible for you to not wear hijaab under any circumstance. If it is possible for you to accelerate your efforts to get married so that you may be able to manage without working under such circumstances, this would be even better and preferable. We share with you your feelings, in the sense of religious brotherhood, of the hardship that faces our fellow sisters in France with regards to the issue of hijaab, and ask Allaah to strengthen you with the courage it takes to stand up to it. By no means is it easy, and it takes great will and determination.
Sheikh Muhammed Salih Al-Munajjid