Buying a digital camera: DSLR vs Mirrorless, also tilt-shift advice?

I will be buying a camera soon and I am seeking advice.

I will be using the camera principally for my environmental work (observing field sites, macro shots of flowers and vegetation, landscapes, wildlife) but I also plan to eventually get into tilt-shift photography as a hobby.

I will be starting around the $500-750 CAD for just the camera.
I understand that mirrorless may be the future and I don t think I really need a viewfinder if the digital display is right there… Not too sure.

Also, I understand that true tilt-shift lens cost ~$2000, so I ll have to save and purchase one later and maybe use cheaper/adapter ones until then but the point is to have a camera that are compatible with tilt-shift lens (Canon EOS or Nikon F series?).

Could you provide a sensible startup package (including must-have lenses) from either Canon or Nikon that can provide my needs for environmental work AND be compatible with tilt-shift lenses?

Any other thoughts or considerations?
Thanks in advance!

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