Can it accommodate a laptop size, up to 16 inches? [ Macbook Pro ] At the back, in the drawer for the laptop... Is there an opening for the power cable/USB cables, etc.?

There are two openings at the back, with cable tie holes for easier cable management and access without compromising security (as seen in attached image). You can explore our 3D model here.

It is compatible with the latest generation of Macbook Pro. We do not know which generation you are using, so please check with the manufacturer or please use this below for reference for your own measurements:

Interior Dimensions of the 1U Security Laptop Drawer:
Width: 409mm / 16.1"
Depth: 338mm / 13.31"
Height: 40mm / 1.57"

MacBook Pro dimensions (currently on their website):
Width: 357.7mm / 14.01"
Depth: 248.1mm / 9.77"
Height: 16.8mm / 0.66"