I think the greatest skill you can possibly learn is how to learn.
With this skill in place, learning other skills is just a matter of time.
You need to find the best way that YOUR mind learns, so don't take it too personaly if your colleagues seem to learn easily while you struggle, it might be that the school method or the teacher is not the best fit for their personality.
When I was a kid, I used to feel stupid and ashamed when I didn't understand what the teacher was saying; many years later, I noticed a pattern: sometimes I didn't understand my teacher, but when that guy was sick and a substitute teacher came over, I would understand everything... and some of my colleagues were the opposite, and really hated the substitute teacher. At the end, it was just a matter of compatibility between me and my teacher.
If you don't understand what your teacher is explaining, try to go online and watch lectures from other teachers.
Find patterns to how your mind likes to learn
Different minds like different styles of learning, besides finding a matching teacher, you should also find patterns to your own learning. Examples: do you learn better before or after exercising? what kind of exercises, intense or light ? Weights, cardio or stretching ? What kind of music helps ? Total silence perhaps ? Do you learn best studying by yourself or with others ? At what time of the day you learn best