Sample nuget.config to show how to add personal nuget server

nuget.config

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <packageSources>
    <add key="NAME" value="FEEDURL" />
    <add key="NuGet official package source" value="https://nuget.org/api/v2/" />
  </packageSources>
  <activePackageSource>
    <add key="All" value="(Aggregate source)" />
  </activePackageSource>
</configuration>

how about credentials??

This is how you add credentials to the nuget.config for private registry name example-nuget hosted in bytesafe.dev:

<?xml version="1.0" encoding="utf-8"?>
</configuration>
  <packageSources>
    <clear />
    <add key="example-nuget" value="https://test.bytesafe.dev/nuget/example-nuget/index.json" />
  </packageSources>
  <packageSourceCredentials>
    <example-nuget>
      <add key="Username" value="bytesafe" />
      <add key="Password" value="xxyyzzzz" />
    </example-nuget>
  </packageSourceCredentials>
    <apikeys>
      <add key="https://test.bytesafe.dev/nuget/example-nuget/index.json" value="xxyyzzzz" />
      </apikeys>
  <disabledPackageSources>
    <add key="nuget.org" value="true" />
  </disabledPackageSources>
</configuration>