It gets old typing in your root password every time you need to run a command that a normal user can’t. Assuming you know the security risks involved, here’s how to make Ubuntu stop prompting you for your root password:
Change this line:
%sudo ALL=(ALL:ALL) ALL
%sudo ALL=(ALL:ALL) NOPASSWD: ALL
Hit Ctrl+X, Y, and enter
/etc/sudoers then press enter. Press Y to overwrite.