Please look at their web-site here.
Here are some rather odd things about it, to pique your interest (my emphasis) . . .
It is registered with the Charity Commission for England and Wales as nbr 1042395 - FRANCO-BRITISH COUNCIL - BRITISH SECTION.
It is legitimate to ask why a charity is getting involved with Defence, which is above all a matter for the national governments. Are charities not required to be apolitical?
According to the Charity Commission, for charitable purposes a political purpose includes "securing or opposing a change in the policy or decisions of central government or local authorities or other public bodies, whether in the UK or overseas". It is hard to see how bilateral cooperation in matters of Defence can be regarded as apolitical, but maybe they are simply not seeking to change the established policy since 1972.
Also according to the Charity Commission, "to be a charity, an organisation must be independent of outside control in a way that would prevent it being subject to the control of the High Court" (I don't understand that either, but I think it means that it must come under the jurisdiction of the High Court).
At this point we really want to know where the FBC gets its funding from. The FBC web-site lists funding sources (as at 21st January 2018):
So there we have it - our Defence policy is being influenced by a charity set up when the UK joined the "Common Market", funded by British and French government agencies and a collection of businesses / businessmen with very large international interests.
The "Leaders" programmes are vaguely defined but could be designed to select and indoctrinate malleable young people to promote unspecified values across the businesses and institutions of the future.
One might think that such an opaque programme should automatically disqualify the FBC from charitable status?
Nowhere does this influence include any democratic input and to retain its charitable status it is honour-bound not to attempt to secure a change in the current policies of government.
The further integration of British armed forces into the EU of M. Macron is progressing unimpeded by any Brexit referendum decision and apparently out of reach of any democratic oversight.