- Shutdown PC completely, Power off PC

- Plug in USB-3-Stick with LinuxMint

- Power on PC

- Look for a very short term message on screen how to boot/start from USB-drive:

- press Function key F2 or  F9 or F... or ESC-key to go to Boot-Menu (e.g. search ACER into Boot)

- is necessary switch off: fastboot and secure boot

- and, or in Youtube search for "start computer from usb stick" or  "Computer von USB-Stick starten" and use deepl.com to translate

- Windows: press Shift-key and hold it during start up

- Use a device

- USB-UEFI Stick

- Apple: Hold ALT-key + NewStartup

- use cursor keys to change in boot-menu first position from HD-drive to USB-drive to start from (mouse does not work yet) 

- wait a few minutes until you see the LinuxMint-Desktop

or start from the beginning. - Press MENU