Install di-netboot-assistant by entering the following commands in the terminal:
sudo apt update sudo apt install di-netboot-assistant
Debian-Installer netboot assistant
di-netboot-assistant is a tool to simplify the preparation of files for TFTP net booting. It downloads and extracts the files needed and takes care of organizing them. In addition, it prepares a top level menu for PXElinux and grub-efi, which allows one to choose from all installed netboot images at boot time. . di-netboot-assistant supports preseeding the installer in order to set up systems completely automatically. . To build EFI boot images, install grub-efi-amd64-bin.