Of course this will also work with other Distributions
This link is for the current stable amd64, download the netboot.tar.gz and extract it.
I changed the folder name to tftp
Login to your Mikrotik Router and upload the extracted folder to your router Files.
Navigate to IP/DHCP Server/Networks and adapt the network, here i used also an NTP server, under Next Servers enter the address from your DHCP Server and under Boot File name: pxelinux.0
Then navigate to IP/TFTP and create an new entry, in IP Addresses put your DHCP range and under real file name enter tftp check allow and read only.
That´s all you have to do.