Troubleshooting MPG on Crashed 2011 Model

I am a college student and due to a combination of COVID and a housing crisis, I had to drive 315 miles to attend classes at my university and 315 miles back to work in my hometown. I would do this ride every week in a 2001 Toyota Tacoma and I was spending just under $200 every time. This cost added up quickly and I calculated being nearly broke by the end of the year if I kept spending this way so I looked for a reliable and fuel-efficient car that was affordable. This is when I started looking into the Prius and set out to find one.

I ended up finding a 2011 Toyota Prius with 160K miles, a good price (4.4k), and it ran smoothly during the test drive. The car was cheap because it was in a minor crash that made it so the right headlight and right taillight had to be worked on. I was able to fix those problems and the car would run smoothly but I did notice that the MPG was nowhere near the 51 MPG reported. I was expecting the car to underperform given that it is ~9 years old and was in a minor crash, but I didn't expect it to be getting 38 MPG.

I have driven the Prius for ~7,000 miles now and have felt some curious attributes that have me concerned. For one, the MPG bar tanks as soon as the meter passes the halfway point. I do not have a heavy foot and I try accelerating as gradually as I can, but as soon as the meter display passes the bar in the middle, the MPG drops to 10MPG, and the car moves at about 8MPH. The speed does not pick up until minutes after and I find myself moving like a snail (32mph on a 45mph road) just to keep it from burning all the gas. I also noticed that when the battery runs low (when the battery icon is at 2-3 bars) the fuel economy coasts at 10MPG regardless of whether I floor on it or lightly touch the pedal. My main and most alarming concern, however, is the hazard signals that are on. The signals that are on are: Yellow tire pressure warning light, Yellow traction control light, Yellow brake system, Yellow ABS, and red "Brake". Lastly, I notice that it does not accelerate well even for a Prius. My girlfriend's uncle has the same model like me and I asked to drive it around. I found that his Prius accelerated much better, did not have huge dips in MPG when accelerating, had a more firm steering wheel, has a more responsive break, and gets much better MPG (46MPG). Testing his Prius is the main reason why I am writing this. I have concerns that there is something wrong with my car and feeling what a well-kept Prius feels like only confirmed my suspicions.

If anyone knows why it is that I am getting such horrible MPG or what I can do to better the conditions, please let me know as I want to fix this now before it gets worse.