If guests have access to the Raspberry it is not that wise to have them having access to the main user account and doing things as sudo <command>.

sudo groupadd -g 1002 guest create a guest user group

sudo useradd -m -s /bin/bash -u 1002 -g 1002 guest create the guest account

sudo passwd guest give a guest password as welcome

groups guest check if the guest does not belong to groups as sudoers

Raspberry OS uses ligthdm as login manager /etc/lightdm/lightdm.conf is its configuration file

comment the line

#autologin-user=<username>

Next time all users must login. Access and login are still possible with ssh and rpi-connect