Workbench setup

I have a series of more than a hundred wooden boxes dimension 30cm x 40cm x 20cm on top of the box l need to engrave various text. Does anyone have any idea how to setup Workbench? In fact, I need such a workbench, which will be adjustable in height. Any solution?

I have seen a few different threads, including one for cutting faces into logs, which I can’t seem to find.

Here us one though.