Social security on spouse visa

Hello,
I am an American and I just moved from the UK to France with my husband who is a french national. I am here on a spouse visa but we also both have work lined up for the beginning of France. I have a few questions and would love some help.

1) As I am here on a spouse visa and not a work visa, I assume that it is my responsibility to file for a social security number rather than my employers?
2) I read somewhere that if you are here on a spouse visa the 3 month wait doesn't apply?
3) As I have work lined up but cannot work until I have my social security number, should I still provide them with my work contract.
4) How do I know where to send my form and all supporting documents? I see that students can do this online but I assume I need to do mine by mail or can this be done in person?

Thank you so much for any advice and support.
Jess