$teams = [
'Russia',
'Kazahstan',
'Ukraina',
'Belorus',
'Litva',
];
?>
<?php if (!isset($_POST['submit1'])):?>
<form action="" method="post">
<select name="team1">
<?php foreach ($teams as $key => $team):?>
<option value="<?= $key ?>"><?= $team?></option>
<?php endforeach ?>
</select>
<div>Goals1 - <input type="text" name="goal1" value=""></div>
<input type="submit" name="submit1" value="Submit1">
</form>
<?php elseif (isset($_POST['team1'])):
unset($teams[$_POST['team1']]);
?>
<form action="" method="post">
<select name="team2">
<?php foreach ($teams as $key => $team):?>
<option value="<?= $key ?>"><?= $team ?></option>
<?php endforeach ?>
</select>
<input type="hidden" name="t1" value="<?= $_POST['team1'] ?>">
<input type="hidden" name="g1" value="<?= $_POST['goal1'] ?>">
<div>Goals2 - <input type="text" name="goal2" value=""></div>
<input type="submit" name="submit2" value="Submit2">
</form>
<?php endif;?>
<?php if (isset($_POST['submit2'])):?>
<h1>Result</h1>
<p>T1 = <?= $teams[$_POST['t1']] ?> Goals = <?= $_POST['g1'] ?></p>
<p>T2 = <?= $teams[$_POST['team2']] ?> Goals = <?= $_POST['goal2']?></p>
<?php endif;?>