3D Print Models 4+

what the hell.

So pretty much I bought the app under the impression that I can make a design from scratch, I have no prior knowledge in graphic design but I got my new printer to work anyhow and I have an assingment at school where I need to work on a display case where I print up some caveman skulls, I saw this app and I was like okay cool lets get it, however when I opened it, it didn’t give me the option to do that, okay big whoop… I can use it for other things then! Then I thought I could maybe attempt to maybe edit the design, nope, as soon as I click on a design, it says I am required to have software to open the files, eventually I just got frustrated and straight up deleted the app, it did not indicate I required pre-existing software to even open the files, I am not happy about it.