First of all, do you have full access to the database with GRANT privileges? If so, then:
In that large text box, type in:
GRANT select,insert,update,delete,create,drop,index,alter,references ON databasename.* TO 'username'@'%' IDENTIFIED BY 'password'
Fill in databasename, username and password with your own information. The "databasename" is the database you want the user to have access to, if you want the user to have global privileges (access to all databases with the privileges as given above) then put "*.*" instead of "databasename.*".