Setting up SSL in Lighttpd

Lighttpd is on Ubuntu 20

# uname -a
Linux www 5.4.0-56-generic #62-Ubuntu SMP Mon Nov 23 19:20:19 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

Some of my issue comes from getting my hosting from arctichost, my cert and domain from namecheap, and my instructions here:

https://aboutssl.org/install-ssl-cer...ghttpd-server/

Not everybody calls the files the same thing.

Here is what I have done:

Artichost sent me two files: server.csr and server.key.

I uploaded the server.csr at namecheap, and they created a mydomain_com.zip file.

The zip file contains mydomain_com.ca-bundle, mydomain_com.p7b, mydomain_com.crt.

Following instructions, I placed all of those file in /ect/lighttpd/ssl/mydomain.com/

Following instructions, I concatenated server.key and mydomain_com.crt into a file called mydomain_com.pem

Now instructions say:
"Once you download the intermediate certificate, copy its contents and paste into a text editor (i.e. notepad).
Save the file as intermediate.crt."

What is this "intermediate certificate" of which they speak? My guess is it's the mydomain_com.ca-bundle.