You will want to edit the file located in /etc/apache2/sites-available/default-ssl.conf
Find the lines and change them to your certificate file names:
SSLCertificateFile /etc/ssl/certs/yourcertificatehere.crt
SSLCertificateKeyFile /etc/ssl/private/yourkeyfilehere.key
SSLCertificateChainFile /etc/ssl/certs/CACert.crt
I then ran the following commands:
sudo a2enmod
sudo a2ensite default-ssl.conf
sudo systemctl restart apache2