How to add icon?

Hello, I found an error on the author page, I want to fix it, but I was confused somewhere and could not understand how it works. If you give me information on how it works, I will understand how it works and I want to fix the existing error.

There is no website section on the author page. When I examined the codes, I saw that a website link was given for the user’s name and I want to fix it. I want to add it next to the Twitter and Facebook icons. I added the necessary codes, but since I could not understand the icon event, it remained there. How can I add the icon event?

As I said, I will create the file as icon/website.hbs. I would appreciate it if you could give me information on how to add the icon and where to get it.

How does the structure here work? For example, I will add the Facebook page as a website. How do we specify the icon in it?

So, what I want to understand is how to add the icon in the place I gave, since I cannot understand the codes there, I would be very happy if you could give me information on how to add the icon.

I temporarily added a Facebook icon, screenshot: