Most employers will recognize your French qualifications as better than the current Red Seal qualification. Some employers will demand a red seal,regardless.
You can "convert" by writing a red seal equivelency test, I think Go2 offers it. I wouldn't do this right now, maybe in a year or so if you really feel you need to.
While your HACCP is valid, I think you should take a "foodsafe" course. This is a very, very basic food handlers course, is only 8 hrs, and costs I think $50. Most employers will want to see this, if only to comply with regulations that demand all food handlers in that kitchen have a "foodsafe' certificate.
You last question is one that I think everyone on this site should read and try to understand. In most of Europe you will need a license or some kind of qualification to operate a food establishment. I know in Switzerland it's called a "Wirtepruefung" and is a full time course of aprox. 1 year. Germany and Austria have a similiar course, and I'm guessing France has something similar as well.
Short answer to your question is no. You only need money and the foodsafe qualification. This is why, I believe, one of the major reasons that 90% of all newly opened restaurants fail within the first year.