Macintosh HD and Macintosh HD - Data Incorrect Configuration

Take it back to the Seller and ask them to perform the below or Request a Full Refund

If neither option is doable, it not falls to you to perform the below sorry to say

The Pervious Owner may have left who know what installed on this computer that could Compromise your Personal Information and Data

They could also place the computer in Lost Mode and Erase the Drive if they choose to do so

Erase a device in Find Devices on iCloud.com

What to do before you sell, give away, trade in, or recycle your Mac - Apple Support (CA)

The previous owner should have performed all the steps in this Apple article prior to selling the laptop:

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

As long as the laptop does not have a firmware password lock and is not being managed by the previous owner with an MDM profile, then you can perform the clean install yourself. A clean install is where you erase the whole physical SSD (Intel Macs only...a bit different procedure for Apple Silicon Macs), before reinstalling macOS. Of course erasing the SSD will destroy all data on the drive so if you have any of your own files stored there, then make sure to get a backup first.

How to reinstall macOS - Apple Support

The problem with the drive layout in your pictures of Disk Utility is someone performed a reinstall or restore incorrectly which left behind an extra "Data" volume. The one in the last screenshot is the extra one...you can tell by its mount point which is in "/Volumes". If you look at the 3rd screenshot, you can see that "Data" volume is mounted under "/System/Volumes" instead which means that Data volume is the one currently being used by your macOS installation. Technically you can just delete the "Data" volume mounted at "/Volumes/Macinothsh HD - Data" as long as you don't need any data stored there.

If you did not perform a clean install of macOS yourself when you acquired this laptop, then I would highly recommend to perform the clean install now instead of just deleting the extra "Data" volume so that you know you have a clean OS free from any nasty surprises left behind by the previous owner. Plus it can alert you to the presence of a firmware password lock or possibly alert you to the laptop being managed by an MDM...neither one is good, so if that is the case return the laptop for a full refund since the seller did not properly prepare the Mac for sale (you will be unable to remove the firmware lock or the MDM profile).

Perhaps it’s a good idea to start from scratch, but it seems that a more innocent explanation-and solution-could be correct.

Often when cleaning up a mac, users mistakenly erase the Macintosh HD volume instead of the whole APFS container. We have seen this here many times.

The solution in that case is simply to delete the extraneous “Macintosh HD - Data” volume.

It should be reasonably clear which is which, but to make sure, select each of the Data volumes in turn and make a note of the mount points.

One of them will be /System/Volumes/Data - that you want to KEEP.

The other will be /Volumes/Macintosh HD - Data

Contr-click a d choose Delete APFS Volume. Done

Interesting and if I were you, which I am not.

Please follow along with the advise from @HWTech

Welcome and if additional questions arise, do post back and either of us will see if we can answer your questions