How do I create a footer for my site?

How do I create a footer for my site?

I tried several different things to add a footer to my website. However, I don't quite understand how to do this, as nothing seemed to work.
Could someone assist me with how to add a simple footer to my site?
I tried addding an image, though I could not move it to the center of the bottom of the page.
Also tried generating some simple html code from an online code generator website; however this didn't quite work either.

All I need to do is put a few simple lines of text on the footer of my site.
Also am not real familiar with how to do a footer.

Thank you for your help.

Joy.