How does one boot to level one? That is interupt the boot to a GUI. I have not been able to get back to a functioning level1 (sudo init 1) so I want to stop on the way up.
I found this from about 3 years ago and it worked. See (Oops I need runlevel 1). It is buried in lots of things that do not work.
"Fortunately, there is a solution that works, which actually gives real single-user access: add a space and a 1 at the end of cmdline.txt, right after the rootwait parameter." I copied /boot/cmdline.txt to a save file and edited adding the 1 and deleting everything past the (now) rootwait 1. (It is no longer the end of the file). Note, before doing this one needs to set a root password. (That is sudo -i then passwd.) Then reboot and it stops at level 1, prompting for the root password. Now one can change the default user (pi) to whatever you want with usermod. then cp the cmdline save file back to cmdline.txt and reboot to graphical mode.