here, i downloaded a few brushes, i have put them in the file with the Adobe's one and when i open photoshop, i dont see them, only the old ones :(

To my understanding, you have to actually add them in photoshop. Go to the Brushes Dialogue (or whatever it's called) and choose the option "add brushes" (or something similar to that )

That's as much help as I can be I'm afraid.

Go to your brushes, hit the little arrow next to the brush size, then on the right of that drop down menu in the top right corner there is another arrow next to where you make the brushes bigger, click that, then click the ones you saved, then hit replace (if you want your current brushes replaced) or append (if you want them added to your current brushes).

Hope this helped :)

Thanks :)
it was using brush then click and "load brushes"