I've personally installed windows on a Mac. The installation is the same as on any other laptop. I can say that this Mac was not new, it was about 9 years old.
I did quick search and found out Apple M1 only released about 4 years ago. That means you're talking about Mac which use Intel CPU, which isn't surprising you can install Windows on it. OP and me was talking about Apple's M series CPU.
Yes, it had an Intel processor. I prefer this processor because all applications run on it, and I don't use Mac because of various limitations.
For Solo Mining I would use ready-made USB devices, but I understand people, because they feel sorry to spend a couple of hundred dollars on this device, which with almost 100% probability will not mine a block.