How to fix "Couldn't include '$autoload_path'. Did you run `composer install`?

Hello Elgg family, I am working on developing a social media platform, with elgg. Now that I have created a droplet with Digital Ocean I now have a working IP address, and it is live because I see the apache default page when I put in the web address. I am now trying to add my elgg folder to my hosting account using file zilla to get the website online. But when I moved my elgg folder to the html folder under var.www/html I am seeing an exception error reading when I try to view it in the web browser

 <?php

$autoload_path = __DIR__ . '/vendor/autoload.php';
$autoload_available = include_once($autoload_path);
if (!$autoload_available) {
die("Couldn't include '$autoload_path'. Did you run `composer install`?");
}
 
\Elgg\Application::index();
 
How can I fix this 
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