changed it like so and so far so good, will let you know the outcome, big shout out to @george1421
kernel tftp://${fog-ip}/os/centos/7/vmlinuz ks=nfs:${fog-ip}:/images/os/centos/7/ks.cfg
initrd tftp://${fog-ip}/os/centos/7/initrd.img
boot || goto MENU