Stalling everyday- coolant, pump, overheating or computer system? Please help! New to forum

Hi everyone,
This is what's going on:

For the last week my 2013 Prius V has been stalling on me multiple times. The check engine light along with the hybrid system light are the consistent lights that come on every time. Sometimes, the coolant overheating light comes on or the overheating sensor. And twice, other random lights flash (brake lights, break fluid, etc.) Every time this happens, I turn off the car for 10-15 minutes and it runs fine, and within the next hour or so all lights turn off (hybrid system and check engine) and the car is seemingly fine until the next day and the process starts over again.

I checked my fluid levels and realized my coolant was down to very little and I filled it back up thinking that was the problem - then, it happened again and again and again. I brought it into the mechanic and he ran the codes and two popped up, one to replace the water pump and one (I forgot exactly the kind) but basically alluding to an issue with the computer system. He checked the recall, and my car isn't part of that and he checked my fluids and did a safety check, did an oil change and reset the computer system hoping that that would take care of it. He said the coolant pump was running and there was a flow and didn't seem to be a problem at all. So, that was yesterday and today I took a drive on the highway and it happened again. First the coolant overheating light came on then the cheek engine light and then the hybrid system light. I turned it off for 15 minutes like I usually do, except this time the car stopped and started when trying to accelerate. I was able to get it running after another 10 minutes of it off and then got about 3 miles and the lights flashed again along with the brake fluid light and brake light and for the first time it didn't just slow down, it stopped. I shut it off again and then turned it back on and is now parked with only the check engine light on.

My question is - has anyone dealt with this? What the heck is going on? All the fluid levels are fine, there's no leaks, no smoke, no smell, no noises...etc. also, what should I do? And what do you think it could be? I'm so confused by this. I saw somewhere mention resetting the code itself, but I'm not sure.

Thank you in advance so much.