How to bypass iCloud lock on a second-hand iPhone 13 Pro Max?

Hello ~ That is the activation lock. If the person/persons that you bought the iPhone from cannot or will not remove it …the iPhone is basically useless to you. If they cannot/will not remove it…return it and get your money back. We cannot help remove it nor can Apple. Take a look here…

Activation Lock for iPhone, iPad, and iPod touch - Apple Support

Also…

The All Too Common SAD Reality of Buying a Used iPad/iPhone

~Katana-San~

You don't.

Return it and get your money back.

If you can't do that, toss it in the recycle bin at your local electronics store and take this as a hard lesson in buying used Apple devices.