OP, no shame in asking a question. I've done a lot of work on my system in the past few years, and here's my opinion. You might find it aligns with some of the things said above, but not with all.
My number one takeaway is that the room is by far the largest factor and best place to put money. John Darko does a nice job talking about his early experiences with acoustics and what he learned. Listen here.
Next, the key to improving sound is to seek out the bottlenecks first. Including the room. Only after those are all taken care of should things like expensive cables, and tweaks come into play. Those are garnishes -- they make a difference, but if the meat (room, speakers, amps, room, DAC, etc.) is mediocre, they cannot help anything.
As for those who say that your new expensive cables will make your (relatively) lower-end system sound better? Well, maybe. But what will be invisible will be the opportunity cost of spending on cables rather than on other bottlenecks.
If I was in your situation, I'd take a breath, send the cables back, get the refund, and research a better way to spend the money. I'm not trying to be unfriendly or snarky or mean. I'm telling you the truth out of respect for the hobby you're undertaking, ostensibly in earnest.