I purchased a used Mac and it has the previous owners login.

I can definitely help you with that! Here's how you can reset your used MacBook Air and log in with your own account:

Rebooting into macOS Recovery:

Shut down your MacBook Air.

Press and hold the following keys simultaneously: Command (⌘), Option (⌥), and R.

Keep holding the keys until a globe appears on the screen.

Release the keys.

Choosing an erase option:

You'll see the macOS Utilities window. Select Disk Utility.

In the sidebar, select the main hard drive of your MacBook Air (usually named Macintosh HD).

Click the Erase button in the toolbar.

Choose a format for the drive. APFS is the recommended format for newer macOS versions.

Give the drive a new name (optional).

Click Erase.

Reinstalling macOS:

Once the formatting is complete, close Disk Utility.

Select Reinstall macOS from the macOS Utilities window.

Follow the on-screen instructions to download and reinstall macOS. This may take some time depending on your internet speed.

Once the installation is complete, your MacBook Air will restart.

Setting up your account:

During the initial setup process, you'll be prompted to create a new user account. Enter your desired username and password.

You can choose to migrate data from another Mac or Time Machine backup during this step, but it's highly recommended to start fresh with a clean system.

Follow the remaining on-screen instructions to complete the setup.

Additional tips:

Before erasing the drive, make sure you have backed up any important data from the previous owner that you want to keep.

If you're unsure about any of the steps, you can consult the Apple Support website or take your MacBook Air to an Apple Store for assistance.

Once you've set up your new account, it's crucial to enable two-factor authentication for your Apple ID to enhance security.

By following these steps, you'll have a clean and secure MacBook Air ready to use with your own account!

[Edited by Moderator]

see > What to do before you sell, give away, trade in, or recycle your Mac - Apple Support

If the original owner failed to properly prepare it for resale as per that support article, then it is useless to you.

At this point you only have two options.

1) Have the original owner property prepare it for resale.

2) Return it to the original owner and get your money back.

You could ask the previous owner for his/her login password and then create your own User Account and password after which you could delete the previous owner's account.

LeanneRN86 wrote:

Thank you! Good to know. I’ll plan on returning it.

You're welcome. Yeah' stay away from iMac's that are sold on E-Bay, Amazon and by individuals.

When shopping for a used or refurbished Mac, it is best to buy from a more reliable seller like Apple, OWC or MacOfAllTrades.

Wow sorry to hear that, hopefully they can help. If not, I'll be sure to remove them from my list.

https://eshop.macsales.com/shop/Apple_Systems/Used/Macs_and_Tablets

Refurbished Mac Deals - Apple