Can you do ....
Absolutely!
Will it take you a few years to figure it out?
Likely...
If you have tons of time, patience, and great computer software skills, you can get there at a very low cost (even free). If not, you will need to make some investment, and even then it will be a very difficult learning curve. Even 3-axis CAM has many people stumped, going to 4, 5, 6+ axes is orders of magnitude more difficult. I would support all the other voices that you should start with 3 axes. If you feel you have mastered that, add a 4th. When you retire and have tons of time on your hands, you will be ready for the 5th.
Not to discourage you, but the trip you are starting on is VERY long. With a perfect machine, the software is very hard to learn. With perfect software, building a machine is hard. Building a machine for the first time, with no knowledge of the software (and assuming you are doing it "alone"), is a heroic effort.
All that said, dive in and have fun! I have, and love it so far.
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