Have someone show you how to remove (well that part is easy) and how to insert RAM. This is a typical failure when the RAM is not well seated or when the CMOS battery finally gets too low.
Since a dead laptop only has a few parts, you want to have someone else check your work.
In the future the rule is, don't fix what isn't broken.
I finally just opened up the back of my laptop, which has never had any issues before; and after hours of YouTube and web help; I only looked at the RAM, by removing it and looking at the back of the RAM stick, then replacing it. I also unscrewed the HDD/SSD port and took it out, looked at it, then properly replaced it. Once I had put everything back in place correctly, and put the back on, I tried to start the Probook. To my surprise, the screen was completely black, as if it has never been turned on. Though, the power button and other normally glowing things were active. After about ten seconds, I could hear the fan intensely spinning as if it was trying to load a massive program, and it continues to stay at that level for a constant rate. So basically, the screen is completely off, but all of the buttons are on. What is the issue, and how do I solve it.