Cannot Add plugins to my wordpress site.

I am not able to see any plugins in my wordpress site. I can’t add new plugins as well. Please help me with this error. I see this error as soon as I go to the “Add new plugin” option in my wordpress admin panel.

<code>Notice: Trying to access array offset on value of type bool in /var/www/html/wp-content/plugins/option-tree/includes/class-ot-settings.php on line 395 Notice: Trying to access array offset on value of type bool in /var/www/html/wp-content/plugins/option-tree/includes/class-ot-settings.php on line 396 Warning: An unexpected error occurred. Something may be wrong with www.remarpro.com or this server’s configuration. If you continue to have problems, please try the support forums. (WordPress could not establish a secure connection to www.remarpro.com. Please contact your server administrator.) in /var/www/html/wp-admin/includes/plugin-install.php on line 183</code>

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