No, you start with a fulltime offer, it's just called "bootcamp". It's our way of doing all the HR stuff (paperwork, medical, legal, etc) + you taking some courses on areas you're interested in specific to fb + you exploring teams and finding one that you will work at.
It's not a strict two weeks, and the process is much more about being pursued than finding a team. For example, a typical bootcamper in NYC will hear from 40+ teams.
Is that still the case? I left earlier this year, but they had instituted a max on the number of reachouts a team/manager can make to minimize the "spray and pray" tactics and bootcamper overload.