Once you have clicked to download, you will get a warning message telling you that you already have the version of macOS installed. Follow this link to get Big Sur (free) on the Apple store. Click Done Step 2 – Get The macOS Install File.It could take a while, so you may need to be patient This will then set up the USB/external drive ready to be used for the rest of the process.Select macOS Extended (Journaled) as the format type.Note: you will need to make sure the drive is name ‘Untitled’ Insert the USB/external drive into your Mac.To format your USB/external drive simply do the following steps.
You can either use Time Machine, if not worried about copying settings and preferences from the old system, or you can sync all of your documents to iCloud before beginning. To create a backup in case anything goes wrong during the process.
