Is sushi so difficult? I've read somewere in the net that sushi is an extremely difficult food to prepare. It will take at least one year just to learn to cook the rice, and ten year to complete the experience.

It's so difficult? To do a comparison, one could prepare a decent home sushi like one can prepare a decent home dish after some years of home cooking?

It's more like a western chef that needs anyway to study and practice for a long time?
Like many crafts which originated in Japan, their sushi training more or less creates sushi artisans.  If you just want to make a snack, you'll have plenty of ability given a basic review of techniques.  You should focus your learning on understanding food-safety, getting the rice right, and making the roll not fall apart.  The rest is just levels of mastery which you need not approach in your kitchen in order to experiment and enjoy a good dish.