Me and my family usually go camping once a year, but lately they don't come camping anymore due to work.. how can I go camping and have fun without them?

Ask around to your friends families and maybe you'll find some adults to take some of you camping. I sure wouldn't go without a responsible adult as too many things can happen. If your parents can't go, then talk to them about it and maybe they can help you out. I'm sure you'll find someone with the time who is willing.