MacBook Pro 2014 factory reset (blinking question mark folder)

Hello,

I sold my old MacBook Pro 2014 13inches to a friend but I needed to reset the computer to factory status.

The following steps took me to a place i’d never expected ending up.

First, I finished cleaning all the files I needed saving. I shut down the Mac and turned on again, this time holding cmd+R at the same time.

A window opens up, it isn’t the Utility window i’d expected, it was a recovery kind of window, allowing me to click on the user that "I know the password for" This wasn’t what I wanted so I clicked in the up left menu, and chose an option that allowed me to reset the mac, erasing the contents of the hard disk and eventually reinstalling an OS version, at least that’s what the window said.

Having clicked and proceeded to resetting, the process finished in some minutes. When the Mac started again, the screen was grey and then a folder with the question mark started to blink.

I was expecting the Mac to reinstall the OS after erasing everything (via wifi) but it obviously didn’t, and instead erased everything, literally everything.

I then proceeded to shut down the computer and pressed the Alt button, this allowed me to choose a hard disk to start the system, except there was no disk to choose from. It instead allowed me to choose a wifi network and connect to it (have in mind that the keyboard is also back to factory reset at this point, for example, my AZERTY keyboard became QWERTY).

After connecting to the wifi network, it allowed me to choose the internet recovery option. After a while, the Mac restarted and the OS X Utilities window came up.

Instinctively, I chose the second option of the menu "Reinstall OS X" (OS X Mavericks) When agreeing to terms and conditions, it asks me to choose the disk where I want to install the OS X, except there is no optios available!!!

I am stuck here, I don’t know what else to do. I need this Mac up and running for my friend to use it.

Thanks in advance.