$parameters = @{
  Name = "myNuGetSource"
  SourceLocation = "https://www.myget.org/F/powershellgetdemo/api/v2"
  PublishLocation = "https://www.myget.org/F/powershellgetdemo/api/v2/Packages"
  InstallationPolicy = 'Trusted'
}
Register-PSRepository @parameters
Get-PSRepository

Name                SourceLocation          OneGetProvider       InstallationPolicy
----                --------------          --------------       ------------------
PSGallery           http://go.micro...      NuGet                Untrusted
myNuGetSource       https://myget.c...      NuGet                Trusted