The description of the roles and the application forms can be found here

Application deadline is January 15th.

YFU CZ pays the participation fee and costs for the IGL, whereas EEE-YFU takes over the cost for all other roles, meaning that if you get accepted, your only cost would be to pay the tickets to the venue near Berlin and back. You tickets will be reimbursed (you will get the money back) at the YES.