I wonder if basic networking is failing (specifically DNS). One of the nvidia.com IP addresses is “216.228.121.209”. Which of these work, which fail?
ping 216.228.121.209
host nvidia.com
If “ping” works, but “host” fails, you simply need to configure DNS in order to get names converted to dotted-decimal format IP addresses. If ping fails, then the router is not forwarding.
Sounds like @Honey_Patouceul has the correct answer. You might comment them out in “/etc/apt/sources.list” or use regular apt commands to disable those. After that and “apt update” to make the changes effective, you might post what packages you need which are no longer available.