<?php
//чтение
$fl1=fopen("kniga.txt", "r");
echo '<div class="div1">';
$n=1;
while (!feof($fl1)) {
    $t1=fgets($fl1);
    if ( $n > 0 ) {
        echo '<h1>'.$t1.'</h1>';
        $n--;
    }
    else {
        echo $t1.'<br>';
    }

}
echo '</div>';
fclose($fl1);
?>