Open fullchain.pem and copy the top half of the file (only the first certificate).
Log in to your GoDaddy cPanel. In the Security section, click SSL/TLS. Under Certificates (CRT), click “Generate, view, upload, or delete SSL certificates.”
Paste the first half of the certificate under “Upload a New Certificate”, where it says, “Paste the certificate into the following text box:” Type a description and click “Save Certificate.”
Under “Install and Manage SSL for your site (HTTPS),” click “Manage SSL sites.”
Under “Install an SSL Website,” select your first domain. Click “Autofill by Domain” and the certificate should populate in the first box. (All 3 boxes may be automatically populated.)
Open privkey.pem and copy the content to the private key field
If the “Certificate Authority Bundle” is not filled in, copy the second half of the fullchain.pem file to the field.