Only existing things can be photographed, for example products as soon as they have been made in the development lab.
Packages and paper stuff are available as blank white for photographing and simple ones can also be drawn in Illustrator or Photoshop. Complex ones need proper CAD application. In addition to proper geometric projections, Illustrator, Photoshop and CADs can give the lights and shadows in 3D mode.
See the following other discussion. There a nonexistent book is prepared for advertising: Imitate a photo realistic rendering of a book cover
Texts, decorative artworks and logos can be inserted. Geometric distortions such as skew and rotate make them to sit on planar surfaces. In Illustrator texture photos, logos, decorative art drawings and texts are easily placed also onto simple curved surfaces. Same in Photoshop.
Highlights and shadows are easy if the materials are non-glossy. They're simply blurred and partially transparent white and black areas with proper blending mode (=hard light).
Highlights and shadows are much more demanding for glossy and translucent materials. With them the skill differences between the people really explode as the differences in the plausibility of the results and consumed time.
CAD software and also Illustrator and Photoshop for simple 3D geometries are great help. Illustrator and Photoshop cant handle reflections and translucent refractions automatically if there ere several objects. Those need hard manual work or photorealistic CAD.
Even if there are no difficult glosses and translucencies, it is not at all easy is to stay consistent in a multi-item layout (=same light, same projection). One must have a diciplined way to work for this.
As already mentioned, purchasing a kit for the layout can be a great help.