Good Evening All-
Sygyzy, just visit any store that specializes in rock-climbing, mountaineering, and rappelling. They have gigantic spools of the stuff available on a "per foot" basis. Most stores will melt the ends for you to prevent unravelling.
Typically, you'll have dozens of choices. You can determine which color, diameter, and material is appropriate for your application. Most of my knives use 2mm paracord in bright colors to prevent loss.
Modern paracord even comes with optional reflective strips woven into the rope. This was originally done to prevent tripping over your lines returning to your tent at night with a flashlight! It does a great job as a high-utility lanyard...especially if you're into spelunking or other activities where you could be in low-light environments. Enjoy.
~ Blue Jays ~