Set this in your /etc/default/grub file:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash loglevel=3 systemd.show_status=auto rd.udev.log_level=3 vt.global_cursor_default=0"
- quiet: Disable most log messages.
- splash: Make sure- plymouthshows the splash screen.
- loglevel: Only show messages with loglevel 3 (- KERN_ERR) or lower. Lower levels are more serious.
- systemd.show_status=auto: Suppress succesfull messages.
- rd.udev.log_level=3: Only show messages with loglevel 3 (- KERN_ERR) or lower. Lower levels are more serious.