<?php

$products = [
	0 => [
		'name' => 'Basic Plan',
		'cost' => 10,
		],
	1 => [
		'name' => 'Standard Plan',
		'cost' => 10,
		],
	2 => [
		'name' => 'Basic Plan',
		'cost' => 10,
		],
	];
	
$_POST['plan'] = 1;

$selected = $products[$_POST['plan']];
echo "You chose,\n Our {$products[$_POST['plan']]['name']} and that costs \${$products[$_POST['plan']]['cost']}";