How to open command line TTY if Ubuntu has been stuck to kill guilty processes? HOW TO START PC IN RECOVERY OR BIOS?

ESCAPE OR SHIFT WHILE STARTING - MORE ABOUT RECOVERY (https://www.maketecheasier.com/boot-recovery-mode-ubuntu/)

F2 FOR BIOS. 

You can get to tty3 by pressing Ctrl+Alt+F3, tty4 by pressing Ctrl+Alt+F4, tty5 by pressing Ctrl+Alt+F5 and tty6 by pressing Ctrl+Alt+F6.

You can then switch between tty3-6 by pressing Alt with the appropriate F-key.

Login with Your current username and password. Commands like killall geany, killall google-chrome, will likely kill the process. Also You can use htop. Inside htop, search for process name You wanna kill by F4, then press F9, press 9 (sigkill) and ENTER.

Finally, you can get back to the GUI with Alt+F1 for the login chooser or Alt+F2 for the logged-in user's desktop.

IF THE GUI been stuck try Ctrl+Alt+Backspace

• Alt+SysRq+E send SIGTERM (termination) signal to all processes except mother init