Try renting out different lenses and camera configurations. check if you prefer one over the other and then check what it costs to buy one. The general rule is
1. Lens is important – 80% of your investment should be on the lens. This will define the family of cameras you will be loyal to and will invest in the future. Camera is just a medium to take photos and most of the work is done by an automatic computer (your brain) + lens. This is how I would approach it.
If Nikon, then
2. Camera can be a basic camera. it is advisable to wait and save up money on a full frame than on a crop sensor. you will hit those ISO limitations sooner than later and you will want a full frame.
Some good combinations like a Nikkor 200-500mm lens paired to a Z6 camera body +FTZ converter is a formidable wild life / landscape lens. I did see that someone was selling their 200-500 in the forum. try to check if it is affordable. Second Step would be to buy a FTZ converter. Third would be to go to a local camera store where you can rent multiple camera bodies and take them on your tours or for your learning. Once you are comfortable with a camera, you would have time to save up on a camera body and you can procure one.
if Sony, I would prefer to first buy the 200-600 lens and rent a camera body until I have enough money to invest in a full frame sony camera like the A7IV which is a good camera for wildlife and others
If its a canon that I am leaning towards, I would invest in their 100-400 lens (Not sure about the latest ones) and rent a camera body like the R6 or the R5 until I have enough to buy a camera body.