Automatic Gain Control
Even though professionals generally don't use automatic gain, 90 percent of the time, it works just fine.
So, as you are learning, it is OK to use automatic gain control--with the understanding that at some point, you'll need to give it up and learn to control audio levels manually.
Back to the cabin with rain pounding the roof. In the audio clip above, the automatic gain control has been turned OFF. Notice that the rain is much quieter in the breaks between the speaking.