You have a "3G" alternator, pretty simple setup. And because it's very popular to swap a 3G into an older vehicle not blessed with one, we have nice diagrams like this:
More info there than you need, you basic takeaway is one big cable to the solenoid/battery. A small one that goes to the the solenoid too. (Some people cheat and connect this wire shorter but the alternoator works better if you connect it as shown). THe last wire goes into the back of the dash and should go to your "ALT" warning light. Hopefully there's a bit of cut wire dangling somewhere you can spot. On Fords this wire is often green with a red stripe.
My batteries are the same way. Normal 12 volt for the engine, and a pair of 12 volt batteries in parallel for the rest of the coach. First picture I found of batteries in parallel. Sorry it says 6 volt, but same idea.
In the picture it makes it like one very strong 6 volt battery. In our cases, 12 volts. If you were using 6 volt batteries you would instead hook them in "series". YOu don't want to do that with 12 volts as you would end up with 24 volts. Smoke, fire, and expensive problems would follow.