I did get stuck and do not know what to do.

You will be playing in 2 different places, Bastian and Carissa. She is in a normal environment and he is on the other side of the corrupted world. I do enjoy puzzle games, but this might be too difficult. Even though I click on everything, I still don't know where the sign on the windows goes. Not only that, but I got so frustrated and the background music didn't help.