What this man said, the program has to render a large number of triangles and shaders in order to create a visual for yourself to edit. This process is best done with a more advanced system. But I will say that the first time loading is the longest. With my system it took me about 20 minutes. Now, the load-up time is about a minute or two. But if you are to take a look at my computer specs you’ll see why it is so fast. Computer specs>> http://valid.x86.fr/cgh3qq <<. With my computer the CPU was pinned out at 99% the entire first load so I was forced to overclock temporarily, but you could be looking at hours upon hours of loading time. Especially without the RAM or graphics to back it up with high speeds.
I’d either do some massive PC building, not upgrading, because you’ll have limited/no compatibility with updated hardware with your current build, or second, I would wait for it to load while putting a limit on your CPU so that you protect it.