unless the milling machine has a servo controlling each axis that can be connected to and controlled by a program on your PC, these hand-operated mills are difficult to use/ This is an automated one, no handwheels:
A while ago, before 3D printing, I took a milling machine and added servos in all four directions (4th being a circular).
The milling machine controller was made in China; and I could never get it to work.