traffic-generator inject function

Hello. I want to generate udp packets containing utf-8 strings formatted according to a simple protocol and send them to a server. I was told that the traffic generator is the tool to use and that the inject function would allow me to send these udp packets. I’m able to send random data with the traffic-generator tool, but I have not figured out how to use the inject function. I also can’t find any sort of detailed documentation on the inject function besides the brief mentioning on this page: https://wiki.mikrotik.com/wiki/Manual:Tools/Traffic_Generator