I think I understand what you mean. So you have created a footballer and want to put him into a team.
You will have to register him, go to 'edit' then 'register player' and select the club you wish to register him to, and at the top of the list you will see 'add player'. Select that then go to created player section and select your created player. Hopefully that's it!
You will have to register him, go to 'edit' then 'register player' and select the club you wish to register him to, and at the top of the list you will see 'add player'. Select that then go to created player section and select your created player. Hopefully that's it!