How to grant sudo permissions to common users in ubuntu?

During the ununtu system installation, the system will prompt you to create a default user, for example, the user name is Zhui. By default, this user has certain management functions, that is, the operation with root permission can be performed through the sudo command. Because Ubuntu does not allow users to log on to the system through the root user by default, this default user is an administrator in the actual sense. But how can I grant sudo permissions to a new common user?

1. Modify the/etc/sudoers file and enter the Super User. Because there is no write permission, add the write permission first.Chmod u + w/etc/sudoers.

2. Edit the/etc/sudoers file and find this line :"Root ALL = (ALL) ALL"Add below"Xxx ALL = (ALL) ALL"(Here xxx is your user name), and then save.

3. Finally, the "no write permission" mode is restored. The file write permission is revoked,Chmod u-w/etc/sudoers.

In this way, xxx users can use sudo su to switch to the root user.