I see, you were looking at this page
I think this is a sign that the text on this page needs to be rephrased. I was involved in the project that led to creating this page, and this page was intended as a response to the same issue that @_az mentioned above (that Certbot isn't the right choice for everyone). The goal of the Certbot project in making this page is to help prospective Certbot users realize that, if they use one of the listed providers, they don't need to use Certbot at all and can use some other (easier) method. We should look at how to make that distinction more apparent.
I'd agree that that page implies that you should be able to use a Let's Encrypt certificate with iPage for free, but it doesn't explain how we know this. I went back and found the reference and it is
which links to
https://www.ipage.com/help/article/enable-your-free-ssl
which is no longer available (!!).
According to the Internet Archive, iPage took that page down sometime in the past couple of years. 
I'm sorry to be the bearer of bad news, but my conclusion is that the Certbot site's hosting provider list that you looked at is out-of-date in this regard and that iPage longer offers support for Let's Encrypt. This also goes to show that we need to institute some kind of review process to check to make sure that web hosts that are listed like this don't change their minds and stop offering Let's Encrypt integrations without our noticing.