Welcome to the forum.
I think the best and first advice anybody can give you is find somebody experienced to go with. I'm sure there's forum members near you to meet up with, or you could google for 4x4 clubs in your area and check their forums for upcoming trips.
A prepared offroader needs to carry spare parts of anything that will likely break, tools to use those spare parts, a well stocked recovery bag with snatch straps, tow straps, a working jack, tire plugs and a full size spare, a good shovel and axe, etc. If you're heading into a remote area alone you also need a personal survival kit, what I call my jump bag - warm clothes, emergency food and shelter, first aid kit, three ways to make fire, lots of water, a firearm if it's legal for you to carry one, a means of signalling for help, maps and compass to back up your GPS, etc.
Knowing exactly what YOU prefer to carry is part of gathering experience as a wheeler, though. For now, I suggest going with another person or group that has experience, and save the solo wheeling until you know what you're doing.