Welcome to the forum! Are you planning to do mostly flat work, 2.5D/3D carvings, plaques with text, etc.? I use Fusion 360 for 95% of my work but that's mostly flat work. For lots of text or any kind of carving I use Carveco. Most here use the Vectric family with VCarve and Aspire being the most popular. Mach4 is controller software that goes on the computer to run your CNC. You won't do any design work on it but that's where you'll run the G-code you generated from your CAD/CAM package.