>>2055255I'd go to your local bike shop and look at basic hardtail mountain bikes and adventure/hybrid bikes. Go test ride whatever they have. The brand name on the bike isn't as important as getting something that's the right size for you and getting something that's assembled correctly. There's options from all the big brands depending on whether you need an MTB for where you want to ride or whether it's more like dirt roads you'll travel: Giant Talon/Roam, Specialized Rockhopper/Sirrus,Trek Marlin/FX, etc., just naming some options from the biggest three brands, but there's a plethora of similar bikes out there.
Also, you really do not need anything special to go off-road. Just needs to be durable. See:
https://www.youtube.com/watch?v=cZk2jV5gJbM 