VIGRUE 16'' Rivet Nut Tool Kit Nutserts Rivnut Hand Tool Set with 15PCS Metric & SAE Mandrels and 300PCS Rivet Nuts Assortment, Rivnut Tool with Rugged Carrying Case for Automotive, Home DIY

Rivnut, Nutsert. It's inserted from the other side. A flange seats against the surface. A tool is threaded into the fitting and it's drawn tight against the back side. Remove the tool and you have a threaded hole. Here's an example. Available in a variety of sizes, standard and metric. The design is kind of like pop-rivets but instead of a center pin that shears it uses a threaded tool to pull them snug, leaving a threaded hole.