Record

Good afternoon! How to record your speech at Audacity in the range from 14 to 20 Hz? Thank you

Unless you are a whale, you don’t. Human speech is typically in the range 150 to 8000 Hz (mostly in the range 300 to 5000 Hz).

Well, we formulate the question differently!
Is it possible to translate audio words pre-recorded in audio into the range from 14 to 20 Hz?

You could slow it down (“Change Speed” effect), or change the pitch (“Change Pitch” effect).
Note that speakers / headphones do not generally go down to such a low frequency.