How to get a value from table in HTML page

Can someone give me a hint or example script how to get a value from table in a HTML page?
I have found that I have to use the fetch() function, but have not found an example how to extract the value from the variable.

Maybe this example could help

var test = await fetch('');
const html = await test.text();
const data = JSON.parse(html.match(/\{.+?\}/s)[0]);
return data.CPM