If you are troubleshooting a Microphone you should confirm that the settings within Windows are configured properly. The best way to test a Microphone would be through the Control Panel's Sound Settings.

If you'd like, you can use the following command to skip directly to the Sound panel, simply press Windows + R and enter 

control mmsys.cpl sounds

Otherwise, follow the steps below

Go to the Windows Search Bar and look for the "Control Panel".

Click on "Hardware and Sound".

Then click on the "Sound" option.

From here, choose the "Recording" tab.

Ensure that you select the correct Microphone device. In the screenshot below, I have both a USB microphone and the laptop's built in Microphone. 

Since the USB Microphone is the default device, only audio from the USB Microphone will be played. to change the default device, simply right click on the intended device and choose "Set as Default Device".

To adjust a Microphone's settings, select the intended device and then choose Properties in the bottom right corner, or by right clicking the device.

From here, select "Levels" to adjust microphone levels. 

If you would like to listen to the microphone through the speakers to test the recording quality, select the "Listen" Tab and checkmark the "Listen to this Device" option. Don't forget to disable it once you are done troubleshooting.

In the levels tab, you have multiple options. The first option, underlined as "Microphone Array" controls the input volume of the Microphone, The sound button to the right controls the mute option for the device.

On the bottom, you may also see an option labeled "Microphone Boost", which as the name suggests actually boosts the Microphone's input level. Note that increasing this will likely cause the microphone to pick up more background noise.

Another common setting that may cause issues is the Microphone Permissions under the Windows 10 Settings app. 

Go to Start → Settings → Privacy → Microphone.

Click Change to enable the microphone access for the device in use.

Under “Allow apps to access your microphone”, switch the toggle to the right to allow applications to use the microphone.