Depends on what you want to do. Either route will work, some people like the idea of starting out with a blank and going from there. Others like the idea of starting from scratch basically.
As far as what you "need" the material can be extraordinarily minimal to quite involved and expensive. As far as what you can get by with on bare essentials. Basically a hacksaw for cutting the shape (angle grinder with a cutting wheel is faster). A few files and a lot of sandpaper can make a functional knife. Having some kind of drill press is something else that would be great to have, but you can likely make a hand drill work. If you wanted to again go super minimal you can do something like a paracord wrap on a handle and not have to worry about holes or how straight they are.
That's about it to get going, everything else like bandsaws, belt grinders, etc just help speed up various steps. If you want to try doing the heat treating yourself you'll need some kind of forge, kiln, or HT oven. But you can always send the knife out to have the HT done.
You're best bet is to fill out your profile and chances are you might find a maker near you who would be glad to help you out in person.