Have I just managed to lock myself out of my own Mac?

[Mildredop]

I was preparing to sell my 2014 MBP. I went into recovery mode, erased the HDD and reinstalled the OS (Mavericks).

I wanted photos of the Mac running Catalina, so went through the set-up process and put in my name and normal password. Went to upgrade the OS and it asked for my password... which didn't work. I've tried every possible iteration I have ever used and it just won't work.

I'm guessing I hit a wrong key during the set-up (I don't remember it asking me to verify the password). I don't want to restart or anything in case it then asks for the password to restart.

What can I do here? I'm guessing I'll need the password to erase the HDD and start again?

 

[hallux]

You shouldn't need the password, just open Disk Utility upon booting to Recovery and erase the drive.

Additionally - see this article on key combinations for installing different versions of macOS, you can even install Catalina directly. https://support.apple.com/en-us/HT204904