can't get past the blinking question mark on startup

There is a process to prepare a Mac to dispose of it. You erased the disk and its operating system. In order to function, an OS needs to be reinstalled. Restart the Mac in the Internet Recovery mode by pressing the Command + Option + R keys on startup to reload the OS that the Mac originally came with.

Was the method from Apple uSed to Erase the Drive

link below

Use Disk Utility to erase an Intel-based Mac

Then this method from Apple to commence the reinstallation

link below

How to reinstall macOS - Apple Support (CA)

Important : in the second step, it will Require a Functioning Internet Connection as it will need to communicate the the Apple Servers to re-download the Operating System

It is suggest to use an Ethernet Cable to Router for a more reliable and speedy connection.

i have tried that command and every other version of that and still have the stupid question mark. i have tried youtube, tech sites and now here. any other suggestions for this problem? mine is a imac desktop if that changes anything