How to get the language of a web page?

Not sure if this is an AppleScript issue or some other tool(s) should be used.

I have a list of web pages on splashthat.com (e.g., https://festadefinaldeanogbs.splashthat.com/) that I want to identify the language and search for keywords on.

Currently I have this list in a Google Sheet because Google Sheet has functions for downloading web pages and identify their language/search for keywords (and can be extended with Javascript to, e.g., clean the HTML). The problem is that splashthat.com doesn’t return the full web page to non-browser clients.

I could tell the browser I view the Google Sheets to download the page but it fails because of cross site scripting is blocked. I also could script a local browser to download the pages but then I have the problem about getting the list from Google Sheets and return the downloaded date into Google Sheets.

If I somehow could activate an AppleScript (or bash or whatever) from Google Sheets to be executed on my local machine, it would work, but that isn’t possible, is it?

What do you suggest?

Thank you.

I have a column with links in a spreadsheet (Google Docs) and want to fill in the cells next to each link with language of the page as well as a boolean that indicates if a certain keyword exists in the linked page.