How exactly to render a model (for example, from Techne)?

I am very confused.

I meant, how to "models" and "renders" relate together?

I cant seem to make sense of their relationship.

Look up Neale Gaming on Youtube. His series should teach you what you need. Id recommend watching all of his videos though. https://www.youtube.com/user/nealegaming

I was trying to render something like the bullets flying from a gun.

Yes I know what youre trying to achieve I have read your threads. I suggest you go through his tutorials from the beginning to the end. He talks about renderers and how to register them properly and how to register entities and what not