About 6 years ago in late December (up to NYD) I went to Cartagena and for a few of days it was windy enough so got a taxi to the kite beach at La Boquilla. There are a couple of kite schools there where you can rent equipment, and obviously get lessons.
I would say it would be a good place to learn. The beach is wide and flat and the water is calm and warm. The wind on a good day can start at 16kts, build up to 25 kts in the later afternoon and blows steady onshore. But not everyday is strong enough to kite. 15 & 17m kites are commonly used.
You can take a look at the beach here:
www.google.com/maps/@10.4711219,-75.4997414,2a,75y,197.59h,87.3t/data=!3m6!1e1!3m4!1s2bvY9zehEuE3YyHaVrZGeg!2e0!7i13312!8i6656Not the prettiest beach in Colombia, but that's not what you're there for right.
Also, this is an Australian forum and Colombia is a long, long way away from here.
You might get better advice from kiteforum. Have a read through this thread:
kiteforum.com/viewtopic.php?f=83&t=2405960