Nexus 7

Hello I have a Nexus 7 and I tried to do a sudo apt-get update on a terminal but it does not like the sudo?
Any ideas on what to do please?
Thank you.

Welcome!

Android by default does not allow super user priviledges.

You have to root the phone in order to get access to the sudo command but it is generally not recommended as it significantly weakens the android design principle and ruins the trust structure that other apps rely on.