I am trying to make some product scene - but I cannot figure out the light. Output format should be - plastic bottle should be little glossy and reflective (same wrap material), PNG transparent file, it should cast a low shadow on ground but still look realistic .
You can count on an HDRI as light source, choose a studio image, increase the Background's Strength (here, 12, but it can be more, or less, and you can add some lights). For the floor use a Diffuse node instead of an Emission, you need a shadow beneath the objects. Result:
The HDRI I've used (check the Polyhaven website for free HDRIs):