Question about truck driving licence and trailer load

Hello, I have 2 questions that fit best into this forum (as I mean) 1. I am thinking about whether I make the truck driver’s license. There are C1/E and C/E. MUss you make all 4 tickets or is it enough if I make the C/E? What does the ticket cost so much? 2. Then I still have a charge for the trailer load on the car At the moment I have the driver’s license B. The following example: I have a car with 1500kg empty weight and 1000kg payload, hook load is unbraked 700kg, and braked 1200kg. Dar f do I drive a trailer with 1500kg zlg total mass, if it is not fully charged and weighs 1200kg? I hope ear can answer me thanks Tobi