The problem
Not long ago, try the dual system, win10+ubuntu20.04, the installation is relatively smooth, can normally enter the system. However, when I updated the graphics driver (proprietary nvidia-drivers-390), I rebooted and couldn’t access the system’s graphical interface, which was stuck on the following page.
The diagram below:

To solve
After that, select ubunru advanced option select l> version of the kernel to boot>ut can enter the graphical interface.
But, it makes me feel bad…
/etc/default/grub

Ctr+Alt+F2

# The original line
# GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"
# Modified
GRUB_CMDLINE_LINUX_DEFAULT=""

After editing and saving, update GRUB:

sudo update-grub

After rebooting, you can finally enter the graphical interface.
The appendix
https://forum.ubuntu.com.cn/viewtopic.php?t=490617