The term sudo in Linux is made to run the super user as root, but login as user (not login as root). The use of sudo users is highly recommended, because it anticipates running command errors (human error) and other security issues.
To add sudo users, first login as root, then :
$ visudo
When there is a choice, select the recommended or easiest one.
Then look for a line like the one below.
## Allow root to run any commands anywhere root ALL=(ALL) ALL
Add the desired user. Suppose the user you want to add is a normal user. Then modify the line to look like this:
## Allow root to run any commands anywhere root ALL=(ALL) ALL biasa ALL=(ALL) ALL
Then save the editor by: ctrl + x then select y
