People are always asking which camera they should get. Go online into any photography discussion group and you will find this question. And the replies are usually telling the questioner to get the camera that the person answering has. I don't know if it is ego? Or if it is some sort of self-valildation that they made the right choice in their selection of camera. Or whatever!
Take a test drive
My advice is to go to a camera shop (yes, there are still a few around), pick up a few different cameras and see how they feel in your hands. Then purchase it locally, too. Ergonomics play an important role for me. One of the reasons I am using the cameras I have today goes back to getting my second camera body back in the early 70s in high school. More on that later.
Once you have found a couple that feel good then try going through the menu systems to see how they are arranged. Many cameras now let you set up your own custom menu screen(s), so that might not be as much a factor any longer.
Technically, cameras from major manufacturers are all good. Canon, Nikon, Sony, Pentax, Fuji, etc. They all have capabilities better than most of the uses we make of the camera. By the time your images are processed and printed, especially if printed in a publication, you would be hard-pressed to be able to tell what camera the image was originally created with.
SLR or Mirrorless?
I am not going to get into dSLR vs mirrorless. Try them both. They each have some advantages and disadvantages. I use both these days. SLRs are usually bigger. Mirrorless usually have smaller capacity batteries. SLRs are usually bigger. Mirrorless are smaller, but the lenses are still large. SLRs are usually quick to pick up, turn on, and start photographing. Some mirrorless cameras take an extra second or two to warm up the viewing monitor (just like turning on a television and needing a couple of seconds for the picture to come on). Try them both and see how they feel and react for you.
Going back to my choice of camera back around 1973, it was between Nikon and Canon. The Canon won out and I still use Canon cameras 44 or so years later. I've often been asked what factors led to that decision. Ergonomics. The Nikon F at that time had its shutter button near the back of the camera and it wasn't comfortable for me to hold and stretch my finger back to the button. Canon had what they called a QL (Quick Load) system for film in the FTb-n that was just introduced. Open the back, drop in the film canister and make sure the film leader reached across to the take up spool. Then just close the back and advance the film. On the Nikon you had to remove the entire back of the camera and attach the film leader to the take up spool. Yes, this allowed for more accessories such as a 250-exposure long roll back, but as a high school student I wasn't going in that direction. A few other things were the big metering prism on the Nikon and the lack of a flash hotshoe (though one could be added over the rewind lever/knob). The Canon had a built in meter with a hotshoe on top of the sleek prism. The Canon had a simple lens mount they called a Breech Lock. You simply put the lens on the camera and a spring turned a locking collar. The lens itself didn't turn so the mount wouldn't get any wear. The Nikon had a more cumbersome mount that involved having to line up an indexing tab for the aperture.
Here are some photos to compare the Canon FTBn that I went with along with the Nikon F.