banner photos

hi,im new to opencart,i would like to change the banner photos,how to do that?also the slider photos....

Ello, mate.
Change the banners is pretty easy, mate. Just access the tab system->design(appearence)->banners and insert the banners that you want.
Then, go to the tab extensions->modules, find the banner modules that you want to edit (slideshow, simple banner, etc...) and link it with the banner that u've inserted on the appearence tab (also set its layout, position, sort order, etc..).