(１) You must take an initial course from the beginning. To give you enough choice there is a 3 months advance period during when you can take a recurrent course.
(２) No, you cannot just take the test. You will need to attend a full initial or a full recurrent course and take the test.
(３) Non-qualified person must not handle dangerous goods. Dangerous goods are to be handled by qualified person or under strict supervision of a qualified person.
(４) No，you are not eligible to take a Category 6 recurrent course. You will either have to take a Category 6 initial course or take a Category 3 recurrent course.
(５) Yes, you must have basic knowledge and experience in international air cargo transportation. A 2 to 3-year experience with international air cargo is desired to understand the DG course as the course covers how to handle and transport dangerous goods by air.