I want to create a scraper using Google Spreadsheets with Google Apps Script. I know it is possible and I have seen some tutorials and threads about it.
The main ide
I made cheeriogs for your problem. it's works on GAS as cheerio which is jQuery-like api. You can do that like this.
const content = UrlFetchApp.fetch('https://example.co/').getContentText();
const $ = Cheerio.load(content);
Logger.log($('p .blah').first().text()); // blah blah blah ...
See also https://github.com/asciian/cheeriogs