How can I setup an SSL?

openssl req -x509 -out localhost.crt -keyout localhost.key \
  -newkey rsa:2048 -nodes -sha256 \
  -subj '/CN=localhost' -extensions EXT -config <( \
   printf "[dn]\nCN=localhost\n[req]\ndistinguished_name = dn\n[EXT]\nsubjectAltName=DNS:localhost\nkeyUsage=digitalSignature\nextendedKeyUsage=serverAuth")

openssl req -x509 -out localhost.crt -keyout localhost.key \
  -newkey rsa:2048 -nodes -sha256 \
  -subj '/CN=localhost' -extensions EXT -config <( \
   printf "[dn]\nCN=localhost\n[req]\ndistinguished_name = dn\n[EXT]\nsubjectAltName=DNS:localhost\nkeyUsage=digitalSignature\nextendedKeyUsage=serverAuth")

proxy-domain: {domain}
bind-addr: 127.0.0.1:8080
auth: password
cert: false

proxy-domain: {domain}
bind-addr: 127.0.0.1:8080
auth: password
cert: false

server {
    # Update this line to be your domain
    server_name {domain};

    # Ensure these lines point to your SSL certificate and key
    ssl_certificate /etc/letsencrypt/live/{domain}/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/{domain}/privkey.pem;
    # Use these lines instead if you created a self-signed certificate
    # ssl_certificate /etc/nginx/ssl/cert.pem;
    # ssl_certificate_key /etc/nginx/ssl/key.pem;

    # Ensure this line points to your dhparams file
    ssl_dhparam /etc/ssl/certs/dhparam.pem;


    # These shouldn't need to be changed
    listen [::]:443 ssl; # if your nginx version is >= 1.9.5 you can also add the "http2" flag here
    add_header Strict-Transport-Security "max-age=0";
    # ssl on; # Uncomment if you are using nginx < 1.15.0
    ssl_protocols TLSv1.2;
    ssl_ciphers "EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH:!aNULL:!eNULL:!EXPORT:!DES:!MD5:!PSK:!RC4";
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:10m;

    proxy_buffering off;

    location / {
      proxy_redirect off;
      proxy_pass http://localhost:8080/;

      proxy_set_header Host $host;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection upgrade;
      proxy_set_header Accept-Encoding gzip;

      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-Host $host;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }

server {
    # Update this line to be your domain
    server_name {domain};

    # Ensure these lines point to your SSL certificate and key
    ssl_certificate /etc/letsencrypt/live/{domain}/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/{domain}/privkey.pem;
    # Use these lines instead if you created a self-signed certificate
    # ssl_certificate /etc/nginx/ssl/cert.pem;
    # ssl_certificate_key /etc/nginx/ssl/key.pem;

    # Ensure this line points to your dhparams file
    ssl_dhparam /etc/ssl/certs/dhparam.pem;


    # These shouldn't need to be changed
    listen [::]:443 ssl; # if your nginx version is >= 1.9.5 you can also add the "http2" flag here
    add_header Strict-Transport-Security "max-age=0";
    # ssl on; # Uncomment if you are using nginx < 1.15.0
    ssl_protocols TLSv1.2;
    ssl_ciphers "EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH:!aNULL:!eNULL:!EXPORT:!DES:!MD5:!PSK:!RC4";
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:10m;

    proxy_buffering off;

    location / {
      proxy_redirect off;
      proxy_pass http://localhost:8080/;

      proxy_set_header Host $host;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection upgrade;
      proxy_set_header Accept-Encoding gzip;

      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-Host $host;
      proxy_set_header X-Forwarded-Proto $scheme;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }

root@strange-hofstadter:/etc/nginx/modules.available.d# sudo systemctl start nginx
Job for nginx.service failed because the control process exited with error code.
See "systemctl status nginx.service" and "journalctl -xeu nginx.service" for details.

root@strange-hofstadter:/etc/nginx/modules.available.d# sudo systemctl start nginx
Job for nginx.service failed because the control process exited with error code.
See "systemctl status nginx.service" and "journalctl -xeu nginx.service" for details.