Error when Setting up a New MacBook Air

Hello, I am trying to set up my new MacBook Air however when I try I am getting the error "The name you used cannot be used" "The name is not available, try a different name"

I have a Macbook from 2013 (which is what I am upgrading from) however I am not looking to transfer any information from the 2013 MacBook to my new 2024 MacBook. I do still wish to use the 2013 model, so I do not want to wipe it entirely or anything.

I currently have Big Sur 11.7.10 operating system on the 2013 MacBook (I cannot do any further system updates.)

I looked into changing the name of my 2013 MacBook, following instructions I found on this forum, however when I click into advanced options under "Users & Groups" the account name is blanked out, not letting me change anything (I was attempting this under a different account, and not the admin account which was advised also)

Is there any other way to keep my current name/details for my new MacBook?

How do people upgrade their MacBooks otherwise? Do they just have different variations on their names? or; Is this because I am not transferring anything from my old MacBook to new?