Install windows and linux on mac?

That will depend on the Mac in question.

If it's an Intel Mac, you can use bootcamp.

click here ➜ Install Windows 10 on your Mac with Boot Camp Assistant - Apple Support

If it's an Apple Silicon Mac, you can use Virtual Machines, like Parallels, VmWare etc... but are constrained to ARM versions of the OSes you are trying to install.

click here ➜ https://www.parallels.com/products/desktop/pro/

He's right. But to install more than one additional OS requires some finesse. I remember there being at least a couple "replacement bootloaders" for Intel Macs that might help. The most current seems to be a project called "rEFInd". As for Apple Silicon Macs, we might have to do some detective work to figure out whether the bootloader can be modified legally and whether any projects are advanced enough and reliable enough to be safe. I would not recommend using any method that does not have quality support and documentation behind it. Otherwise, VMs are the most reliable method to try out as many OSes as you want.

--Nate