Hi there and welcome to imore. There isn't a trash can. You can delete apps by long pressing on them until they all wobble, then clicking the X that appears in the top corner of the app you want to delete. If you have a file inside an app then the app would be the only way of deleting it.
Otherwise, you can connect your iPhone to your computer and sync he sections and items you want from the menus that can be accessed by the little phone icon in the top left of the screen.