MacBook

Hi demotriea,

Thanks for posting in Apple Support Communities.

We understand that you need to install the mac operating system on your Mac. You will need to download Snow Leopard and create a bootable drive to install the software.

Download Mac OS X 10.6.8 Update v.1.1

"Use Terminal to create the bootable installer

1. Plug in the USB flash drive or other volume that you're using for the bootable installer. 
2. Open Terminal, which is in the Utilities folder of your Applications folder.
3. Type or paste one of the commands below into Terminal, then press Return to enter the command. Each command assumes that the installer is in your Applications folder, and MyVolume is the name of the USB flash drive or other volume you're using. If the volume has a different name, replace MyVolume in the command with the name of your volume.
4. When prompted, type your administrator password. Terminal doesn't show any characters as you type. Then press Return.
5. When prompted, type Y to confirm that you want to erase the volume, then press Return. Terminal shows the progress as the volume is erased.
6. After the volume is erased, you may see an alert that Terminal would like to access files on a removable volume. Click OK to allow the copy to proceed. 
7. When Terminal says that it's done, the volume will have the same name as the installer you downloaded, such as Install macOS Monterey. You can now quit Terminal and eject the volume."

Use the steps in Create a bootable installer for macOS.

Regards.

If you're just doing it to get GarageBand 6, it was bundled with iLife '11 so you can install it from there onto any mac running MacOS 10.14 (Mojave) or earlier because it's a 32 bit app I think.

I get it, GarageBand 6 has so many things 10 doesn't have like ducking.