nVidia 510 driver made um 21.10 - kernel 5.13.30 - system unbootable

Dual boot computer um21.10/win10. Installed the kernel update to 5.13.30, reboot fine. Upgraded nvidia 470 to 510, and can not even get to the login window. It constantly is flashing like it is in a loop. I do still have grub, and can get into windows. Grub seems to be a dead end for getting to a command line login. I got to root login by the advanced options, but I don't know to get to my super user login.

Read about removing nvidia drivers, and then reinstalling 470, or the add the dev repository for marco...but I can't get to the proper login. How do you navigate from grub to a user command line login? Feeling pretty dumb...

Got into the console, but the Marco patch didn't help, and it seems all the nvidia packages have disappeared. Going to try switching to the default graphics driver.

In case anyone is like me, and have mainly used linux through a gui - to bypass the gui and get to the user command line/console here are the steps:

-Boot holding "shift" key (bios) or Esc key (uefi) until grub appears
-On grub selection screen press the "e" key while your "ubuntu" is highlighted (to edit parameters)
-Using arrow keys to navigate for the line beginning "linux", and has "vmlinuz" in it as well. Place cursor at end of line by pressing "end" key add a space followed by the number "3"
-"ctrl + x" or "f10" to boot to text mode then enter user name and password and you are there.

I ended up removing the nvidia 510 driver

sudo apt purge nvidia-driver-510
sudo apt autoremove

Then installed the previous nvidia driver (in my case 470)

sudo apt install nvidia-driver-470

reboot, and it's fixed