FBA related question (for EU market)

Hello,

Does anybody know how FBA works? We have 12 marketplaces and are currently selling as FBM. If I switch to FBA, where do I send our products? Do I have to send them to 12 different locations, one for each marketplace, or is there a central warehouse that allows us to use FBA for all marketplaces?

Any advice would be much appreciated. Thanks!