If you want to factory reset a storage device like an USB drive or a SD card, you can follow along this method. I'm going to use Windows 10 for this tutorial , it's probably working in older versions of Windows. For MacOS and Linux, I'm going to make a specific tutorial.
So first of all, type Powershell in windows searchbar, or press the windows key on your keyboard and type Powershell. As you can see on the image below. And press Enter.
After that, you're going to have an open Powershell window. Click on it, and write diskpart.And press Enter again. Windows going to ask if you want to give permissions to the application, click yes.
Now that you are in diskpart, type list disk to show disk currently plug in your computer. For this tutorial, I'm using an 8gb micro sd card, so I'm going to choose disk 2. Select your disk using select disk + the number, in my case select disk 2.
Now that you've selected your disk, we can remove everything that's on it even partition, by just typing clean. After that, you need to create a new partition otherwise your disk gonna be completely useless. So type "create partition primary", and then you can format your disk by typing format fs=fat32 quick, it's going to take some seconds.
And that's it for this tutorial, you now have a completely reset storage ! This tutorial works for every possible storage device that you can plug to your computer. Hope this was useful !