I get error when i run "sudo apt-get update" and also showing wifi adapter not found
rr:1 http://security.ubuntu.com/ubuntu bionic-security InRelease
Could not resolve 'security.ubuntu.com'
Err:2 http://packages.ros.org/ros/ubuntu bionic InRelease
Could not resolve 'packages.ros.org'
Err:3 http://in.archive.ubuntu.com/ubuntu bionic InRelease
Could not resolve 'in.archive.ubuntu.com'
Err:4 http://dl.google.com/linux/chrome/deb stable InRelease
Could not resolve 'dl.google.com'
Err:5 http://in.archive.ubuntu.com/ubuntu bionic-updates InRelease
Could not resolve 'in.archive.ubuntu.com'
Err:6 http://in.archive.ubuntu.com/ubuntu bionic-backports InRelease
Could not resolve 'in.archive.ubuntu.com'
Reading package lists... Done
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/d... Could not resolve 'in.archive.ubuntu.com'
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/d... Could not resolve 'in.archive.ubuntu.com'
W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/d... Could not resolve 'in.archive.ubuntu.com'
W: Failed to fetch http://security.ubuntu.com/ubuntu/dis... Could not resolve 'security.ubuntu.com'
W: Failed to fetch http://dl.google.com/linux/chrome/deb... Could not resolve 'dl.google.com'
W: Failed to fetch http://packages.ros.org/ros/ubuntu/di... Could not resolve 'packages.ros.org'
W: Some index files failed to download. They have been ignored, or old ones used instead.