what is macOS Base System

Hi lizmarin1718,

No. Here is my guide:

1. Once you are in macOS Recovery, verify you are connected to WiFi in the top right corner.
2. Go to Disk Utility.
3. Select "View" in the toolbar > "Show All Devices".
4. Select your main hard drive. This will either be "APPLE SSD...", "APPLE HDD...", or "Fusion Drive". DO NOT select Base System.
5. Click Erase, and input the following exactly: 
6. Name: Macintosh HD
7. Format: APFS
8. Scheme: GUID Partition Map
9. Click Erase (THIS WILL ERASE ALL DATA)
10. Quit Disk Utility
11. Go to the reinstall macOS app.
12. Follow the prompts, and install on Macintosh HD.

Cheers,

Jack