Still getting the same code check Engine light is on almost everyday

Here is what was on the readout from the ODB gun;

po300 random
multiple cylinder misfire


symptoms.....rough start, i have to press the gas to get it to start
:::low mpg about 13 to be exact, was getting near 18::::dies while stopped sometimes::::

No shops want to service this. And I am not a mechanic:::need help

Thanks