Certbot SSL certificate doesn't work for port 8000

i have installed an SSL certificate into my app using certbot, when i visit bushnaq.group, the connection is over https, if i visit bushnaq.group:8000 (NodeJS running server), it's actually running over http, when i sending request from client https://www.bushnaq.group to server http://bushnaq.group:8000, it will block the requests because of mixed-content (the content must be served over HTTPS)