Mac Forums

Can someone plz help me??when I sign into my account I can't see my desktop/dock. The screen is all gray & the only way I can access to safari is by clicking the apple on the upper left corner & then going 2 recent items & then I can open safari.& somethings something comes up & it says that the disk is full & I need 2 delete files 2 make space but I can't do that since I can't see my desktop/dock...Is there a keyboard shortcut that will make me open the finder so I can go 2 files & delete them 2 make space.and is there also a shortcut 2 go 2 trash so I can empty it.