First

This is the first text that i write in italki
Well, one of the things that I like is the music because I think that it is the most important art in the world or maybe one of the wonders of the world. Actually and since very years old is present in all places and country For a very long time it has been present everywhere and in all countries, because it has the power to transmit sensations and feelings. I believe that the music is indispensable for the humans and ever always will be.

In English, using "years old" is usually specific and has a number, like "I am 20 years old".  If it is not definite, you can say something like "for many years".

Very interesting!