Multiple issues(?)

I have a 2007 Prius that I believe has multiple issues, but I'm unsure. Last year, my prius stopped working while I was driving, all lights came on, loud beep, no acceleration, brakes were hard, no power steering. I got it towed home, replaced the 12v battery, drove it to a Toyota dealer, and they said the issue was the water pump and water valve assembly, so I paid them $1,400 to fix it. It drove more or less fine for less than a year (about 11 months, but a several month break in there), then the 12v battery died. I could barely get it to hold a charge long enough to drive 10 minutes to home, it wouldn't turn back on when I parked. It sat for 2-3 months. I replaced the 12v battery, and it drove fine for about a week. After a few days, the dash lights stopped working again (this has been an ongoing issue ever since I got the car a few years ago), but I unplugged and plugged back in the battery, and the dash worked for a couple more days. This also came with a check engine light, I took it in to get tested, and it gave codes P2601, and C1241. Now, yesterday, as I parked, the car made a loud beep, and the brake became hard to press. It sat for a couple hours while I waited for my mom to get off work and allow me to follow her home. I unplugged and replugged the battery, hoping to get the dash lights to come on. They did not come on, but the brakes worked fine for the whole drive home, albeit they sounded weird (for example, it made a sort of chugging noise when pressed lightly). Keep in mind, since the dash lights are off, the only light I can see is the Check Engine light and turn signals.

Some other things I noticed recently are that the "weird noises" the car makes are a bit weirder than normal lately, some noises are higher pitched, sound like they're dying, or last much longer than usual. There's also a high pitched (but faint) electrical noise that I never noticed before. I'll attach a video in which you can hear one of the noises that is lasting much, much longer than it usually does. It happened for several minutes, minutes apart, even when the car sat for a while.

The thing I don't get is why am I getting codes for the thing I just had fixed less than a year ago, and only drove the car for about half of that time?

I tried to add as much detail as I could to paint a full picture, sorry for the post being so long, but I greatly appreciate you taking the time to read it!

Link to video: