The title says it all. I will happily answer any questions that you need. I’m sorry, I’m new to networking and things like this.
Welcome to the Let’s Encrypt Community 
The webroot is the complete path to the folder containing the files at the “root” of your website. Usually it’s where your homepage is located.
So it’s a file location?
Normally it’s a directory location.
If you point us to your website we can possibly tell you which web server software you’re running and guess some likely locations. Do you get your website hosting through a company or are you running your own server?
No thanks. I understand now.