About some errors when using the order of "apt-get update" in Jetson TX2 device

When I use the instuction of “sudo apt-get update” in Jetson TX2 device,it displays some errors like that:“Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/xenial/main/binary-arm64/Packages 404 Not Found [IP:91.189.91.23.80]”.So I also find some answers about this,using the order of"apt-get remove .*:arm64 dpkg-remove-architecture arm64".But when I use"sudo dpkg --print-foreign-architectures",the output is “amd64”.So can I really use the instructions mentioned above to fix my errors??

The TX2’s architecture (native) is arm64. amd64 would be foreign to a TX2, and absolutely worthless.

When you see the IP address with port 80 listed and “404 Not Found” it implies the server you searched on was reached and the server searched for a document, but failed to find the requested document. Your networking is valid, but the package being searched for (perhaps because the server is only amd64 and doesn’t have arm64) is not there.

If you go to the basic part of the URL leading up to the specific package you’ll see what that server actually has:
[url]http://us.archive.ubuntu.com/ubuntu/dists/xenial/main/[/url]

Unfortunately, that server provides binary packages only for amd64 (an ordinary 64-bit desktop PC native architecture) and i386 (an older 32-bit compatibility version…technically a foreign architecture even on a PC).

It may be that the server once had arm64 binaries, or it may be that the repository was searched due to some default search order…don’t know. Do you have a specific package you are interested in? Otherwise it would seem that repository needs to be commented out or disabled. One exception would be that many source packages would be valid from this server, but you’d need to compile them yourself.