Welcome to the club! Here are my thoughts:
Software
VCarve is expensive, although VERY easy to use and top-notch, I would purchase right away if I had the money. If you don’t want to jump in and spend that money (save it for endmills 
), I would look at Carbide Create or Fusion360. Fusion360 is CAD and CAM combined, and a lot of the hobbyist community uses it. Fusion is also pretty popular within the Onefinity community. I got my machine a few months ago and have been using Carbide Create, works nicely although it’s missing a few key features such as ramping, nesting and a few others. I recently tried HSMExpress for SolidWorks and I’m liking it a lot so far.
As for software, what type of projects you will be working on? If it’s primarily fine woodwork, then I would go for one of Vectric’s products. If it’s more “parts and assembly style” stuff, Fusion360 is probably better as it offers parametric modelling.
I personally use my CNC (mainly) for the latter, machining a lot of “mechanical” parts so for me 3D modelling isn’t as important. I just need something for CAMing, as I use SolidWorks for the design aspect of a project.
Other Comments
Just like lathe chisels, get good, high-quality endmills. Don’t skimp out as these play a huge part in whether your project is a success or not. Here is a thread discussing some good brands for cutters. I would pick up a standard square endmill, a flattening bit and a vee-bit to get started.
The probe isn’t a must to get started, just use small jog increments and “zero” it either by eye or with a piece of paper.
Before you start milling, make sure the white collars on the drive screws are tight, mine wiggled lose and popped off during one of my first cuts (scaryyy!), and make sure your router is properly trammed.
Hope this helps!