Can I use my microphone in libreoffice?

I’m looking for a way to plug in my microphone to libreoffice, so to speak. so that I can speak the words instead of typing them in. If this is now even possible I’d very much like to know.

The microphone is the hardware. What you are more likely asking about is speech recognition software that can work with LO. This thread from early 2013 discusses speech recognition software options.