Just got sober and need to fix my computer to stay busy

I have been sober for 4 days after many years of drinking. I'm hoping to fix my computer to fill some of my down time and get some of that sweet sweet dopamine I'm lacking right now. I have a gaming pc I bought off marketplace last year that I loved using. It's has a sapphire nitro graphics card if that matters. Sorry I'm a noob but I would be happy to answer anymore questions. The first thing that happened was it seemed like it stopped running smoothly one day and maybe the next day it stopped sending audio through the HDMI cable. Everything it tried failed to make sound work. Then a week later it stopped booting and just brought a screen that said something like Failed to boot .. something Bios. I went into that menu and tried to figure out what was wrong but needed help so I googled it. The next time I flipped the switch the computer didn't turn on at all. There were yellow indicator lights on the motherboard but the RGB on my fans wouldn't light up either. Someone at work told me it could be the power supply. Any idea what's up? Thank you and sorry for the layman explanation.