Tried on HP Victus
The grub is lost because the windows is set as default for login in BIOS.
If you set Ubuntu as default grub will be back.
Go to BIOS settings (F10) and Boot Settings and OS boot manager and put ubuntu on top.
You get grub back (you can select between ubuntu and windows then)
Select Windows [Didn't Work]:
Hold Shift+Restart
After Restart Again F9 and Windows and got to:
Advanced Options > Command Prompt
and do:
X:\Windows\System32> bootrec /fixmbr
X:\Windows\System32> bootrec /fixboot
sometimes this gives error: Access is denied.
if so, do this
X:\Windows\System32> bootsect/nt60 sys
Then do:
X:\Windows\System32> bootrec /fixboot
Repair Grub : Do this before deleting partition [Did but didn't work]
Might need to do it by creating an installation media in USB (F9) for boot options HP Victus.
X:\Windows\System32> bootrec /fixmbr
X:\Windows\System32> bootrec /fixboot
sometimes this gives error: Access is denied.
if so, do this
X:\Windows\System32> bootsect/nt60 sys
Then do:
X:\Windows\System32> bootrec /fixboot
AnyDesk Fix: (display server not supported)
sudo gedit /etc/gdm3/custom.conf
WaylandEnable=false
AutomaticLoginEnable=true
AutomaticLogin=$USERNAME