How do I activate a pending SSL from Namecheap in linode (wrrgames.net)

It sounds like the CNAME record is a method of proving that you own a domain. If that isn't working for you, you can try one of those other methods of verification from that guide.

If you've already completed that step, you'll then want to follow one of our guides for setting up SSL.

It's difficult to tell from the information provided, but you may need to first create a Certificate Signing Request, though that part may have been included in the steps taken with NameCheap. If you didn't already do that before, I recommend reading through that guide.

Otherwise, all that should be needed is getting your cert files onto your server and configuring your web server to use SSL. You'll want to make sure the certificate files are in the right place based on where your webserver is looking for those files. For example, if you were using Ubuntu or Debian with Apache2, that guide shows the following configuration for /etc/apache2/sites-available/example.com.conf:

<VirtualHost *:443>
    ServerAdmin info@example.com
    ServerName example.com
    ServerAlias www.example.com

    DocumentRoot /var/www/html/example.com/public_html/
    DirectoryIndex index.html

    # SSL configuration
    SSLEngine On
    SSLCertificateFile /etc/ssl/certs/example.com.crt
    SSLCertificateKeyFile /etc/ssl/private/example.com.key
    SSLCACertificateFile /etc/ssl/certs/ca-certificates.crt  #If not using a self-signed certificate, omit this line

    # Log files
    ErrorLog /var/www/html/example.com/log/error.log
    CustomLog /var/www/html/example.com/log/access.log combined
</VirtualHost>
<VirtualHost *:80>
    ServerName example.com
    ServerAlias www.example.com
    Redirect permanent / https://example.com/
</VirtualHost>

You'd want to make sure that SSL is on and the path to the files that Apache is looking for are correct and contain the crt and key you got from NameCheap. You can cat out the corresponding files from these lines of your own configuration to make sure that they look right.

SSLCertificateFile /etc/ssl/certs/example.com.crt
SSLCertificateKeyFile /etc/ssl/private/example.com.key

If you can tell us more about any specific errors you're seeing and any guides you followed, we may be able to provide a bit more guidance. Otherwise, I'd recommend using Let's Encrypt with Certbot for the easiest way to enable HTTPs traffic on your server.