Is't possible to start a server with frogbots?

So a friend can connects to my server and we all can play against bots? like ffa?

yes, you can
gamedir fbca or smth

if you're using eQuake or fQuake package, simply make a shortcut with the cmdline -gamedir fbca, or startup quake and type gamedir fbca, then do exec server.cfg (important), the server will load up dm6 in 2on2 mode, to change this, do 4on4/2on2/1on1 in the console, have your friends connect and chose there team and add bots after that through addbot command.
if 4on4 the teams will be red and blue, if 2on2 it will be jams and your team most likley =)

GL!