How can I drive 12v LEDs from my Arduino Nano?
You cannot directly drive 12V LEDs from arduino. If driving only one LED, use a transistor. Otherwise use a ULN2003 IC to drive multiple LEDs.

Better off, order the normal LEDs. You will save area on your RC device.

Here is a video that will hep you using ULN2003. In the video ULN2003 is used to drive relays, but you can replace them with LEDs.

Using a transistor:


Using ULN2003: