You don't run both OS's at the same time. You only run 1 at a time (you choose which one you want to boot into when you start the computer or reboot; you're prompted with a boot menu to choose which to boot into). If you want to run multiple OS's at the same time, then you'd need to install/run the OS in a VirtualMachine, which WILL cut your performance, because each OS (the host OS and client OS), takes part of your resources. Dual/Triple/whatever booting doesn't harm your performance because only 1 OS is running at any one time.
And Zmatt means that you'll have to do a bit of work to learn how Linux works, mostly.
And Zmatt means that you'll have to do a bit of work to learn how Linux works, mostly.