If you have an XP machine then it probably has an IDE connection inside, so all you have to do is remove the hard disk and move it into the XP. Open both boxes and check if the hard disk connections are similar, if yes then it is a pretty simple work. I can't give you step by step instructions, but if you need it you may need to check your manual or try to find information on the net. Look for "IDE hard disk upgrade" or something similar. Of course, the work is done with the power off, once you power it on you have to check in BIOS if the hard disk is present, maybe you have to change some setting in BIOS. If it is present in BIOS then just boot your XP and your "new" hard disk should be visible as a new drive, probably D if you only had C before. Once you can see it under XP you can explore and try to find what you need. Beware that you might still not be able to run the software due to lack of driver. Not every software can be run by simply clicking on the exe file, some need proper installation.
If you need to connect the har disk to a USB then you probably need something like this:
I am running Mach3 on laptop under W10 Pro, using UC300 motion controller and that works fine. If you are unsure you can run your old XP with Mach3, assuming it is a desktop PC. Mach3 works fine with the parallel port on an XP desktop, so you can test your machine before investing in a new PC and motion control and Mach3 license. The demo version of Mach3 works fine if you just want to test the machine and don't need USB.