Can we create a website for other web sites scrapping?

I am thinking about creating a website for web scrapping of other websites. In clarifying the idea I will use web-scrapping site (for the website to scrap other websites) and to-scrap site (for an exemplary website from which the user wants to get data):

So the idea is that the user gives the URL of a to-scrap site to the widget on the web-scrapping site, and the widget shows the to-scrap site. Then the user can select an HTML block (similarly like in devtools of web browser), and gets data from it (e.g., text or number).

Is it possible? I have used several web-scrapping libraries, but always with desktop apps. I have looked for a way for "retrieving a site on another site", but no luck there. What do you think? Thank you!