Well, as you have the machine already, you might as well try to get it working.
I use the same machine, bought from ebay many years ago, before I knew about the engraver‘s café. You might take a lead from the GraverMax manual (https://grs.com/wp-content/uploads/2019/08/004-041_MaxMate.pdf) for the procedure of the pressure regulator adjustement. The machines look similiar (also inside), I guess the GraverMax was the original for the chinese copy.
My machine was non-functional when it arrived. It leaked like hell, the compressor didn‘t almost never shut off. I had a new valve body made from igildur, fixed the broken moter regulator, built a new fine-regulation pedal, fitted an external pressure regulator and so on. Those machines could work, but there is a big „chance“ factor in it.
Good Luck
every newbie should be required to read your reply
Ralf