user is not in the sudoers file

Follow these steps:

1. Open a konsole terminal window.
   
   

2. Switch to the root user if you have access, by running:
   

   su -

   You might need to enter the root password.

3. Once you're the root user, you can edit the sudoers file with a command like this (replace "your_username" with your actual username):

   visudo -f /etc/sudoers

   (If this command isn't found, install it first apt-get update && apt-get install sudo once sudo is installed, you can add your user to the sudoers file as previously described using visudo.
   
   

4. This will open the sudoers file in the text editor (usually vi or nano). Be careful while editing this file, as any mistakes can lead to system instability.
   
   

5. Navigate to the section that looks like this:
   

   ## Allow root to run any commands anywhere
   root    ALL=(ALL:ALL) ALL

6. Below that section, add the following line to grant sudo privileges to your user:

   your_username ALL=(ALL:ALL) ALL

7. Save the file and exit the text editor.
   
   

8. Finally, test if sudo is working for your user by running a simple sudo command:

   bash

   
   

   sudo echo "Hello, I can sudo now."