CIH or OHC DIFFERENT? More questions

Hello guys, I have a Opel Omega A Caravan with a 2.4 liter machine in front of me. But now I realize that it is a “CIH” machine. Since I have no idea at all about Opel, I would like to check this out and clarify myself. I also have questions about what the advantage of this machine is (2.4 liters), but also the disadvantages. What is waiting for me? I know, it’s absolutely used cars, you shouldn’t be so picky, but don’t want to drive the car straight to the scrap. because I have no idea……. I would be very grateful for answers. Could also be that I ask further questions in the course of the answers……