thibaultj-p wrote:
I think I have to repair my disc though disc utilities / first aid, but I'm wondering if this will erase my hard drive (I have the most important files backed up, but not everything; I know that if a file is damaged then it will be gone anyways. I just want to know if using disc utilities / first aid erases the hard drive).
Running DiskUtilitiy— First Aid does not erase anything. Full stop.
Boot into Internet Recovery (Option Command R) and from the dropdown menu: Utilities> Disk Utility> run the First Aid on your Macintosh HD (and the "Macintosh HD-Data" volume as well if Catalina/Big Sur/Monterey) If errors are found and repaired, run again until no errors reported.
Disk Utility>View>Show All Devices The best sequence is —
• Volume level
• Container level
• Parent drive
Recovery (both M1 and Intel) — https://support.apple.com/en-us/HT204904
https://support.apple.com/guide/mac-help/use-macos-recovery-on-an-intel-based-mac-mchl338cf9a8/mac