As some have already mentioned, here's list of things to look for. Since for landscape and wildlife photography you are dealing with low light allot of the time due to wildlife being most active early or late in the day, and sunrises and sunsets are/can be low light situations.
-mid/upper range DSLR (Canon 70D and up or Nikon's equivelent)
-lenses with the lowest "F" number that you can afford, eg. 200mm F2.8. The lower the F number for any given lens, the better it will preform in lower light and help keep the image from getting "grainy" looking with digital noise. This can be the most expensive part of your camera gear. The lower the F number, the higher the price but better quality.
-make sure the lens (or camera body in some cases) has vibration control. "IS" in Canons, "VR" in Nikons. This help greatly in getting sharp shots while either you are moving or the light is low. The Canon "L" series of lenses are also the best sealed for the elements to keep water and dust out of them.
- plan on two lenses at least, one for landscapes (anything with a range around 10mm to 100mm) and one for wildlife (range of 100-400mm).
-as mentioned, and external microphone with wind control foam for better sound if you are planning to have voice audio in the videos.
I personally use a pair of Canon 7Dmkii's and a Canon 6D, all with battery grips for the extra battery capacity and to fit my bigger hands. Lenses, range from a 15mm fisheye to an EF 400 F2.8 IS. I don't do video though, only occasionally, I'm into the still photo's.
The lower F stop numbers also apply to video quality, the lower the better.
Start with the best/highest level of body that you can afford and the best lenses that you can afford because if you really get into this, you'll be upgrading too soon and it will only cost you even more with more purchases!
and don't start with a bag that is "just right" as you will very quickly out grow it and end up with a collection of bags!
The lenses are an investment that will last you years and through several upgraded/worn out camera bodies, so they are the best place to spend the extra amount on.