Is there a way to do like keyword 'e' in grub

[myxal]

I don't think the exact functionality is possible to do in ipxe, as here the menu entries are simple jumps to a label in the script - you don't necessarily have them 1:1 associated with kernel image and parameters.

What you probably could do is to have another item toggling a true/false variable if the user wants to edit the kernel + command line, and use the read command if it should prompt the user. A variant with no menu is actually used as an example in the docs:

Quote:Allow user to edit a kernel command line before booting

Code:

set cmdline selinux=0 console=ttyS0,115200n8 console=tty0
  echo -n Kernel command line: ${}
  read cmdline
  chain http://my.web.server/vmlinuz ${cmdline}