It isn't difficult to modify the Jeep mildly.
But modifications beget modifications...
You should really take a hard look at your needs. Do you anticipate a Paris-Dakar trip? Might need a lift and larger tires, stouter bumpers, winch, lower ratio gearing, auxiliary transmission cooler, dual batteries, ARB refrigerator, roofrack, snorkel, HID & LED lighting, etc...
Poke around on this forum and see what the members have done in their own garages and driveways. Be honest with yourself about your needs and create a timeline for the build. We'll get you through it.
Bear in mind that a stock Jeep can go many many places; some of the gizmos we choose to add make it easier, aid recovery of stuck vehicles, or allow us greater comfort levels.
You might enjoy the Expedition Portal Forum
; we have quite a few members from GB, Oz, Africa. You can get a feel for what works in different environments.
My Jeep just has tires/wheels, 4.56 gears, springs from an Unlimited, bumpers, & winch. I'm beginning to wish for lockers and a little lift as I find my limits.