XT6 Dash gauges for oil pressure and voltage aren’t very accurate. I wouldn’t even look at those.
How old is the battery? It may have 13 volts for 2 milliseconds and bad cells brings it too low almost instantaneously.
Charge the battery then try to start the car once or twice if it’s below 12 after that then it’s fried
Use quality jumper cables or power pack - does it turn over then?
Give power directly tk starter post - what happens?
huge issue with jumper cables is cheap cables with anything short of exceptional connectivity won’t flow enough amps. people all the time misdiagnosis a car because jumper cables didn’t start the car but the issue was cheap cables or not good enoug connection