GamerCore
Android Enthusiast
The SIM card tray is located at the very top of the Moto G5 Plus. Simply insert the included SIM card removal tool that came in the box (or use a small paper clip) and press it firmly inside the hole until the tray pops out.
Pull the tray out and on the back you'll find a spot to place your SIM card (it's clearly labeled as "SIM"). Place your SIM inside until it firmly snaps into place. Once you're done, insert the tray back inside the slot until it's completely flush with the device.
And that is how you insert/remove the SIM card on the Moto G5 Plus.