Depending on the ratings of the "teacher" as well as the amount and quality of the videos.
I followed a course (didn't pay for it, I received it as a gift) for FB ads and it helped me a lot. The in-dept details were amazing and I find it really interesting to follow.
I assume it's worth your money, if you would else spend it on a "night out" or "some game" you will end in 24 hours.
If the 12 euro's isn't worth it in your opinion, for example being unable to buy food, then don't do it. If you can afford the 12 euro's, I'd recommend to seek a course that suits your expectations well and go for it.