Lauris
To make this work properly you need to track the footage (if it is footage) and then from the track create a 3D scene with the table and put your character on it. Create a light to match the footage and then render out a shadow pass and comp the lot in After Effects.
HTH
Tickety boo and ta ta for a bit...
Gazzamataz
https://www.gazzamataz.com