I don’t have any disk to select when it asks me to select one
I tried to reset my macOS sierra
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You need to follow these instructions: Use Disk Utility to erase an Intel-based Mac - Apple Support
Just prior to Step 4, you need to select the View menu > Show All Devices. Then, you need to select the internal storage device. "Device" in this context means a hardware component with an immutable name such as "APPLE SSD... MEDIA".
That's what you need to select, and erase.