iWeb

No and you don't what to keep using iWeb. It's been discontinued for over 5 years now and is not compatible with Catalina and only partially compatible withy Mojave.

You would be best served to migrate to web design app that is supported and compatible with the late3st web standards. There are many possibilities out there. Just search the forum for "iWeb alternative" or "iWeb replacement".

One that many migrated to initially was EverWeb because it has a similar interface and you could drag and drop into the page while building. Another reason many liked it was that they could start out with a blank canvas. Many of the other apps only offered predesigned themes.

There is no app that can read published iWeb pages and edit them. One that fan read them is Flux but the pages are so complex that it's impossible to figure out how to edit and make it work.

Didn't you have a backup of your boot drive prior to your iMac crashing. If you did you could restore the iWeb folder that's in your Users/Home/Library/Application Support folder.

The free version is the same as the paid version. Don't remember what the restriction on it are, something like only publishing to the hard drive. Try it first before paying for it to make sure it is what you want.

I believe that EverWeb saves and published to the EverWeb folder in the User/Library/Application Support folder.