It is hard to give specifics of how to add switches unless you can say what electrical/electronic hardware you have, a link to documentation would be even better.
Screens can be edited with the screen editors available, there is a learning curve but there is a section on the forum for screens and also there should be a video or two describing the basics.
the need for 24v outputs would likely require you to use relays, but again unless we know what hardware you use no one can really advise.
Hood