Audio recording without using the microphone

It had Realtek software instlled but no option to use the IDT Internal micophone

Hello. As you said, your laptop has Realtek audio so it is unclear what you mean by "IDT internal microphone". Dell does not use both Realtek and IDT audio hardware in the same laptop model.

Here are some other ways to record besides using the built-in mic.

> External mic. Because the Inspiron 7537 only has a headset jack, you cannot use a regular computer mic that would have a TRS plug, but instead you should use a headset with a TRRS plug that looks like this:

A "headset"  is headphones with a microphone. You can also use a regular mic that has a TRS plug if you obtain an adapter to convert it to a TRRS plug. The adapter is called a "Headset Buddy".

> A usb mic.

> If you want to record a stereo signal, you cannot do that through your headset jack because its input is only mono. To record stereo, you need a usb audio adapter that has a "line-in" jack. Don't get one that only has a mic jack because that will only be mono too.

I want to record from a file

> If the file is already in your computer, you can internally record within the computer by selecting "stereo mix" as the default device within the Recording tab of the Sound properties. If you do not see stereo mix, right click within the blank area of the tab to open the context menu and select to "show disabled devices". (You have to have your Realtek audio driver installed.)