Fusion360 and Linuxcnc are not the same thing, although they do work in harmony .... on diferent computers as one uses windows and the other Linux as an operating system.
Fusion is CAM software or computer aided manufacturing, meaning it can draw models that can be output as gcode for use with machine controllers, that iz where Linuxcnc comes in play as it is a machine controler that uses the output of fusion to drive the machine and make those parts a reality.
As for drives and other stuff, there is a wide variety of them that can be used with Linuxcnc, from 10€ a piece for TB6600 ones to 150€ a piece for Lam Technologies.
Some more information on the machine would help, like what is it suposed to do, what are you using for the actual movement ( belts, ball screws, allthread, rack and pinion ), etc.
Changing the collets is not something you do automatically on a machine but even that has been done to some degree with Linuxcnc, the tools can be changed or the tool holders, and that is quite easy to set up in Linuxcnc.