So I tried removing the line that prints hello world into the console every time I load a map that I added ages ago so I can test if this whole endeavour will even work at all. For some reason, even after building it and replacing the old files in my mod folder, it still prints hello world, supposedly using some invisible code that I clearly don't know about. I decided to ignore it and download the unified SDK you recommended and I found some code that pertains to a "helmet" in the items.cpp file of that SDK, it's structured similarly to the code that adds the suit battery into the game but missing a few things and it could be unfinished. I'm wondering if all I have to do is just copy that code into the items.cpp of the project I'm using and that will be it, but I sincerely doubt that.
There's also something else, I went back to that tutorial and there's a part there that I don't really remember doing. It tells you to change the platform toolset to another version. The projects I had downloaded were using a different version to what was mentioned in the tutorial so when I tried changing it for each project, a lot of the code was made non functional and there were red and yellow blocks on each line which I assume is bad. Building the whole thing printed errors into the console so I decided to switch back to the platform toolset I was using before. It would really help if I could get some extra clarification on all this.