Replacing Receptacle With GFCI Outlet
Harper’s rule: Anytime you install a GFCI receptacle, the very first thing you do is find the terminals marked LOAD and lay a piece of tape across those terminals. The reason is to protect yourself from using them by mistake.

You do not ever use the LOAD terminals on a GFCI unless you know exactly what they are and how to use them. In fact I recently installed an older GFCI unit and the manufacturer had indeed installed a label across those terminals saying exactly that.

In your case, that makes installation pretty easy.