If you have some beginner to moderate trails around you, you can start wheeling without all the mods. A set of All Terrain tires will get you far without having to worry about having separate winter tires, and summer MT's.
Once you get the hang of it, you will find you will want protection (skidplates, sliders, steel bumpers - likely in that order) and will think about installing a lift and bigger tires, which will make the moderate and harder trails a little easier (and ease the worry about the smashy smashy on the rocks.)
Welcome!