Thanks for the help! Here’s the content of my config.php file, found in /var/www/html/nextcloud/config/config.php:

<?php
$CONFIG = array (
  'instanceid' => 'ocqwzk5v4jkq',
  'passwordsalt' => 'F49DxXdKC9Rfmao/FbDSpg8AXF87yG',
  'secret' => 'hNgBS5HBfGPwa4sYIf/lN/Bl0JV474LkxsciZITDNtN5hopU',
  'trusted_domains' => 
  array (
    0 => '192.168.1.101',
  ),
  'datadirectory' => '/var/www/html/nextcloud/data',
  'dbtype' => 'mysql',
  'version' => '15.0.10.0',
  'overwrite.cli.url' => 'http://192.168.1.101/nextcloud',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost:5432',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'kwright',
  'dbpassword' => 'wizard',
  'installed' => true,
);

As seen above, the path to the Nextcloud root is /var/www/html/nextcloud. It is owned by the www-data user, and its permissions are 755. The database has been created, with the name nextcloud.