I own a Jeep (TJ) that I've built up for off-road excursions. I'd like to clarify about how these vehicles handle dirt, country roads, or mountainous terrain compared to bikes: Jeeps are nowhere as good as bikes.

Crazy, right?

It's not like what the marketers would love you to believe, but it's true. A 1.5 ton, four wheeled vehicle will struggle in all kinds of situations where light two wheeled vehicles will have no trouble at all. There's a reason why you'll see so many people standing around in videos of us four wheelers trying to make progress: walking is faster and easier! Pushing a large, heavy box through difficult terrain is a large part of the fun of a Jeep.

My recommendation for a bike is a gravel or all-terrain bike (ATB). Today's mountain bikes are built for fast descents, very rough terrain, and large jumps. They're amazing on certain trails but, IMHO, not the best for dirt and gravel tracks. Gravel and ATBs are also more flexible with mounting points for things like racks, cages, etc for outdoor excursions. As a bonus, they're cheap right now. Gravel was all the rage during the pandemic and now stores are overstocked. You can get a great deal on new or last year's models from your local bike store.

Or, if you really want that four-wheeling experience, take look at recumbent quadricycles. They're quite unique! With fat tires they'll float over just about any soft surface.

As others have stated, do not go to a box store or online with very limited exceptions. A LBS will generally employ a mechanic who knows what they're doing, will stand behind any issues that arise, and can work on the bike after it breaks in. You'd be lucky if a Walmart employee manages to put a handle bar facing forwards.