I've set up a local http web server. You can use another web server mirror if you want.

default

DEFAULT      vesamenu.c32
PROMPT       0
 
MENU TITLE PXE Boot Menu
MENU INCLUDE pxelinux.cfg/graphics.conf
MENU AUTOBOOT Starting Local System in 8 seconds
 
# Option 1 - Exit PXE Linux & boot normally
LABEL bootlocal
	menu label ^Boot Normally
	menu default
	localboot 0
# Option 2 - Run WDS
LABEL wds
	MENU LABEL ^Windows Deployment Services
	KERNEL pxeboot.0
# Option 3 - Go to Linux menu
LABEL linux
	MENU LABEL Linux
	KERNEL vesamenu.c32
	APPEND pxelinux.cfg/linux
# Option 4 - Go to tools
LABEL tools
	MENU LABEL Tools
	KERNEL vesamenu.c32
	APPEND pxelinux.cfg/tools
 
# Option 3 - Exit PXE Linux
LABEL Abort
	MENU LABEL ^Exit
	KERNEL abortpxe.0

linux

MENU TITLE Linux Operating Systems
 
MENU INCLUDE pxelinux.cfg/graphics.conf
 
LABEL debian-1004
	MENU LABEL ^Debian 10.04 Netinstall
	KERNEL iso/debian-10.04-netboot/debian-installer/amd64/linux
	APPEND vga=788 initrd=iso/debian-10.04-netboot/debian-installer/amd64/initrd.gz
LABEL fedora-server-32
	MENU LABEL ^Fedora Server 32
        KERNEL iso/fedora-32-server-netboot/images/pxeboot/vmlinuz
	APPEND initrd=iso/fedora-32-server-netboot/images/pxeboot/initrd.img noapic inst.stage2=http://repo.local.ribbed.us/fedora-server-32/ ip=dhcp
LABEL centos-8-2-2004
	MENU LABEL ^CentOS 8.2.2004
        KERNEL iso/centos-8-2-2004/vmlinuz
	APPEND initrd=iso/centos-8-2-2004/initrd.img noapic inst.stage2=http://repo.local.ribbed.us/centos-8-2-2004/ ip=dhcp
LABEL ubuntu-server-2004
	MENU LABEL ^Ubuntu Server 20.04
        KERNEL iso/ubuntu-server-20-04/vmlinuz
	INITRD iso/ubuntu-server-20-04/initrd
	APPEND root=/dev/ram0 ramdisk_size=1500000 ip=dhcp url=http://repo.local.ribbed.us/ubuntu-20.04-live-server-amd64.iso
LABEL mainmenu
	MENU LABEL ^Go back to Main Menu
	KERNEL vesamenu.c32
	APPEND pxelinux.cfg/default

tools

MENU TITLE Tools
MENU INCLUDE pxelinux.cfg/graphics.conf
 
LABEL memtest86
	 MENU LABEL ^memtest86
	 KERNEL iso/memtest86/ISOLINUX/MEMTEST