Thanks.
I can start my webserver. After I enter:
SSLCertificateFile "/etc/letsencrypt/live/marketinglab.biz/cert.pem"
SSLCertificateKeyFile "/etc/letsencrypt/live/marketinglab.biz/privkey.pem"
SSLCertificateChainFile "/etc/letsencrypt/live/marketinglab.biz/fullchain.pem"
on wp-config, my website is not working.
Here’s the cert I have.