To do so, press Ctrl+Alt+T, which will open a new terminal window with a command prompt in most Linux desktop environments. If you’re not using a desktop environment, you’re already at a command prompt, so proceed to the next step. A Password: line will open below the command prompt. When the password is accepted, you’ll be brought back to the command prompt as the root user.  If you type the password incorrectly, run su and try again. Passwords are case-sensitive. An Enter new UNIX password: line will appear below the prompt. The password you type will not appear on the screen. You will see a message that reads “password updated successfully.” This will log you out of the root account.
टर्मिनल (terminal) विंडो खोलें: कमांड प्रॉम्प्ट में su लिखें और फिर ↵ Enter दबाएँ: आपका मौजूदा रूट पासवर्ड लिखें और फिर ↵ Enter दबाएँ: Password लिखें और ↵ Enter दबाएँ: नया पासवर्ड लिखें और ↵ Enter दबाएँ: नए पासवर्ड को फिर से लिखें और ↵ Enter दबाएँ: exit लिखें और ↵ Enter दबाएँ: