Advice needed for a switch controlling 3 switch states at once?
Your diagram isn't all that clear and you may be able to use a DPDT switch but, just in case, you can get 3PDT (Triple pole, double throw) switches like this: -



It has 3 sets of change over contacts and should suit what you want. The keyword is "3PDT". Another view is this: -



It's the one on the right. And below looks like one you can buy: -





Maybe you actually want this: -