Greetings,
I understand your project description.
I think you want to collect all websites from the email address from your collected thousands of websites URLs.
I am an expert in Web search, Web scraping, Email marketing, Excel, Data entry, and more.
So, I think I can do this task very effectively.
If you hire me Then I trying to complete this task 100% accurate.
So, please discuss more over the chat.
Thank you.
Tanmoy.