If you don't want to make this yourself, you can find the easy-to-use template here.

In this tutorial, you will learn how to create a low-poly background effect in Adobe After Effects. This effect requires a plugin, but if you don't have the plugin, you can still purchase and use low-poly background elements that work with any editing software.

However, if you have the Trapcode Mir plugin and want to create this effect on your own, start by creating a new full HD composition with a frame rate of 30 frames per second and a length of 10 seconds. Next, create a new solid layer where you can apply your low-poly background. Go to your effect Trapcode and apply it to your composition. Here, you will see your geometric shapes, which you can adjust in size and density.

Check out this video to learn more about creating a low-poly background effect.