Simple php code to count visitors on one page and display in footer

I'm new, and learning. I only have a single digital product. I want to display the total number of purchases made, in my footer (on all pages). I have not been able to find a lightweight plugin that can do this, nor any code that works. I am using Woocommerce and since I only have a single product, buyers are taken directly to the checkout page once they click on "Buy". Once their payment goes through they are taken to a Thankyou page. I thought that if I can count the number of visitors who visit this Thankyou page and display that, it would give a pretty accurate number of purchases. I am able to do everything except that I do not know how to count the visitors on just that single page. My page is id=376, but how could I call that? Here is the php code that I'm trying. I think I need to swap the fgets($file, 1000) with the actual page id???

$path = 'C:/xampp/apps/wordpress/htdocs/counter.txt';

// Opens counter.txt to read the number of hits.
$file  = fopen( $path, 'r' );
$count = fgets( $file, 1000 );

/*$count = fgets( $file, 1000 );*/
fclose( $file );

// Update the count.
if ($page_id == 376) {
$count = abs( intval( $count ) ) + 1;
}
// Output the updated count.
echo "This product has been purchased <strong>0000{$count}</strong> times\n";

// Opens counter.txt to change new hit number.
$file = fopen( $path, 'w' );
fwrite( $file, $count );
fclose( $file );```

source https://stackoverflow.com/questions/67926603/simple-php-code-to-count-visitors-on-one-page-and-display-in-footer