Gateway: Change titles in footer of theme


I am using the grav Gateway skeleton. I am using linux/debian.
I am a complete novice at working on a website, and using Grav. I am learning as I go along, with a bit of help of course.

I’ve managed to change in the footer the " About the Gateway Theme" with VI.
But I can’t find “Archives”, “Keep in touch” and “Find what you need”.

Where would I be able to find those ?

Thanks in advance