Please explain the usage?

[kaceo]

I am transitioning from Certbot to this, but I'm only a user so the explanation is missing big gaps for me.

In certbot I run scripts to (1) generate domain names, (2) renew domain names. I don't have to generate keys, or know where the files are stored. I can place the scripts into CRON jobs and let it autorenew every month, with no extra housekeeping. I have 30 names and wildcards on my system.

Is it correct to say that this package requires additional scripting in another language if I want to achieve the equivalent workflow? What are the key files for and why is it necessary to create them for each domain? How can I renew domains automatically?

Sorry if all of these are obvious but as users I really need handholding.