The default login account of Raspberry Pie is Pi. In order to unify security and usage habits, the steps to modify the default Pi account are as follows:

First, you need to enable the root account:
sudo passwd root
At this time, you will be asked to enter the password twice for setting

After setting the root password, exit the current pi user (I will not quit, but restart decisively):
sudo reboot

Log in as root and unlock root:
sudo passwd --unlock root

Modify user first:
usermod -l yourname pi

Modify the group again:
groupmod -n yourname pi

Then change the home directory:
mv /home/pi /home/yourname

Set the home directory:
usermod -d /home/yourname yourname

OK, now you can log in with your new account. The data is completely original pi.
Finally, for security reasons, disable root.

sudo passwd -l root

PS: Is the default password of the new account raspberry