I upgraded to Ubuntu 20.04 today. Now, after restarting it goes to GNU GRUB 2.02 and then I cannot go further. Please help
Solution 1:
If you didn't use manual partitioning, so your boot is in UEFI mode.
Type reboot after grub>, press Enter, after restart press F12 (or something else, depends on your laptop or PC) go to your boot menu, set your boot option UEFI.
Ubuntu 20.04 use boot on UEFI mode not LEGACY. (if you use minimal installation from mini.iso image, you can boot it on LEGACY mode)