Double cast on question

I began by learning the single cast on and have moved on to the double cast on. However, I’m a little confused because the end of the double cast on is just a single loop. Is that correct? How do I begin knitting from that - and do I treat each loop separately or do both of them together?

Treat the first loop as a stitch.

Oh I just realized I was doing the double cast on wrong! I watched the video again and saw that you put it through the left loop then the right and bring it back through the loop. Now it works, thanks!