You're close: What you want is to add another layer to your hash, here are a couple hints:

my %Rolodex = {
    BobSmith => {
        name => "Bob Smith",
        phone =>"123-456-7890",
    },
    JimJones => {
        name => "Jim Jones",
       phone =>"098-765-4321",
    },
};

for my $personKey ("BobSmith", "JimJones") {
    print "Name: %s, Phone: %s\n",
          $Rolodex{$personKey}{name},
          $Rolodex{$personKey}{phone};
}

my @BobSmithk = keys(%{$Rolodex{BobSmith}});
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