IMO, if you have no equipment right now, going mirrorless is a no brainer. Which body to get really depends on your wants, and your wallet. If money is no object, go for the Z8, or Z9. If most of your shooting does not require the latest, greatest auto focus, the Z7ii might be a candidate. It is currently on sale for $2,000. It has a 45 MP sensor, as well as a lot of features that lend themselves to a serious amateur. The 24 MP of the Z5, Z6ii/iii or Zf is definitely adequate for most images, but the higher resolution sensors are a godsend on the occasions when you need to crop. I do a lot of wildlife and macro photography and frequently need to crop my images significantly. I find the 45 MP sensor to be a good fit for me. The Zf is slightly cheaper than the Z7ii does on sale now, the main advantage of the Zf over the Z7ii is better autofocus for moving subjects.
If money is tight, you might consider the Z50ii. It's brand new, so it doesn't have much of a track record right now. It is geared more toward new, or more casual users, although a good photographer can make the most of any decent camera system. Some of the downsides are a 20.9 MP sensor, and, being a crop sensor, you will likely accumulate a few crop frame lenses that you will eventually want to replace down the road if you decide to switch to full frame later on.
I made the switch from DSLR to mirrorless a few years ago. I wasn't entirely happy with the electronic viewfinder for the first week or two. After I got used to it, I found that I definitely preferred it to the optical viewfinder on my old DSLR. The Z mount lenses are also a step up in quality IMO. Nikon is quickly getting out of the DSLR business, and will no longer be developing any new DSLR bodies or lenses. They continue to sell new DSLRs and lenses, but the models offered for sale is quickly shrinking.