When I go to pokestops and spin the coin it picks up all items if I press them or not. Is there a way to leave items and not pick them up? For instance I want to pick up pokeballs, but leave the revives.
No, there isn't a way to avoid picking up certain items. However, you can delete items from your inventory. When you are viewing items, tap on the trash bin for the item that you'd like to reduce the quantity of. You'll then see a pop-up asking how many items you'd like to discard. Select the appropriate amount you'd like to get rid of and tap yes.