Top-of-page / scroll-back-to-top button

I’m looking for one of those buttons (like a circle with an upward-pointing arrow) that one can place at the bottom right corner of the last section or in the footer, which gets you back to the top of the homepage – is there such an element available and how is it called?

I’m using your basic theme without a starter site for this website. I would prefer to do this without installing a plugin.