Important is to have some elementary photographic skills as well as a certain level of equipment to be able to create excellent pictures who give us a "wow" effect while watching. I started all with a first careful set of pics with one puffer coat owned by a co-worker over 10 yrs ago, I used a small Nikon 1 mirrorless camera with a 1" sensor (which isn't even second choice). Better than typical compact digital cameras of that time with their even smaller sensor sizes like 1/2,3", but miles away from what a 36 x 24 mm full frame sensor can give you. I had no special portrait tele lens for that small cam, only zoom lenses with rather low speed. It was a beginner's thing in fashion portraits.

Later I used full frame DSLRs like my old Nikon D4 pro body with the AF-S 1.8/85 mm G lens for F-mount. That lens has great image quality and I got lots of beautiful fashion portraits with it. Some shoots had been done with only that lens at all.
In 2020 I changed to Z mount mirrorless with Nikon Z6 and Z6 II bodies and I also used their better video capabilities to enter the filmmaking scene (well, not professional level filmmaking, just amateur short films as good as I can do). The F-mount 85 mm lens was replaced by the Z-mount 85 mm lens with same speed f=1.8. The best 1.8/85 so far from Nikon, sharp crisp images even when shot wide-opened (as far as your subject is in focus and you don't shake the camera too hefty

Now my no. 1 camera body is a Nikon Z9 which is a big and heavy pro body (like my former D4). The biggest part of my fashion shots is in portrait orientation and for that I really love a specific second shutter button with some function buttons and command dials for portrait orientation, the Z9 is the only body feat. that as a built-in grip (the other bodies like Z8, Z7 II, Z6 II and III need a certain battery grip attached).
And my no. 1 lens now is the big and heavy (and expensive) 1.2/85 mm Z Nikon lens which is a beast. It is one stop faster than the much smaller 1.8 version. It is more or less useless when you shoot a classic upper half of the body portrait frame or even closer, you have to stop down even an 1.8 lens to get the whole model sharp. We don't talk about microscopic differences in image quality of these two lenses at f)2.8 or so.... no, the real strength of the big 1.2 beast is shooting a complete body portrait showing the person from head to toe (wellies

Well, as budget is a serious topic for many people for sure let's talk about alternatives being much more affordable.
For full frame Nikon shooters my second recommendation is the Z 1.8/85 which I used for four years. Get it if you look for very high performance wide-open and without the need for adapters. There are cheaper 1.8/85 lenses from China on the market (like Viltrox), but they don't reach the quality of the Nikkor and you can face some AF probs esp. after a body firmware update.
So my advice if you are on limited budget and want to enter the Nikon Z system is:
- get a used Z6 or Z6 II body and a used Z 1.8/85 in good condition. You can get that combo for about half of the price of the Z 1.2/85 or even less.
It could be there will be an affordable Z mount 1.4/85 non S-line Nikkor in the future, Nikon brought 1.4/35 and 1.4/85 non S-line primes this year. Don't expect the maximum image quality wide open if that lens really will come, but it could be an alternative when you want an 1.4 speed while still being on budget limitations.
If you have an F-mount DSLR and want to stick with the DSLR F-mount system, the AF-S 1.8/85 G is the budget prime to go for. If you can afford some more, go for the 1.4 version. Used in good condition about 700-800 EUR (German 2nd hand market prices). You can use both on a Z body with FTZ adapter, but for me that adapter thing isn't really a pleasure. Functionally at least on par with a DSLR, mostly even more accurate in focus bc a mirrorless doesn't have the front focus/back focus probs coming from separate AF modules in DSLRs. The AF cells of a mirrorless are on the sensor.
If you are even more limited and can only get a smaller APS-C size sensor body (Nikon "DX") like Z50 or Z fc, Nikon doesn't have impressive primes for the smaller sensor. You could try it with a third-party prime like e.g. Viltrox with 56 mm focal length, a 56 mm f=1.2 lens would be a full-frame 1.8/85 pendant. Or you could use a "nifty fifty" 50 mm lens with at least f=1.4 to get a proper APS-C size portrait lens.
So you see there are different ways to enter the "serious" potrait and fashion photography sector depending on your budget and needs. Most important is, if you wanna do that, do it, ask your friends and family, do it and get experience. Do some exercises like identical shots with different f-stops to see how the depth-of-field is changing and what's best for your subject depending on the distance to the background. Train your eyes with different posings, different locations and different views on one specific location. Look at other photographers' pics and get inspiration. Shoot in raw instead jpg and learn to optimize your pics in postprocessing (the Nikon Studio NX software for raw converting is a great tool for free). Exposure compensation, white balance, brightening shadows, it's so great what raw development can offer to get the best possible image results.
And last not least - of course you can be proud when you get great images and you want to show the world your work. But think of it, not every model wants the pics being spread all over the net esp. when she wears fashion which is a fetish for some people. Privacy is something you should always have in mind. And that's the reason why I don't post my fashion shots in public. At least no uncensored ones.
