Hesitation issue, car running poorly P0300, random misfire

Hesitation problem at 2500-3000 rpm cannot get much higher than that when driving, gas mileage has dropped. I have just replaced the spark plugs and wires. Still a p0300 code random misfire. Cleaned the mass air flow sensors before that also had a ignition control module code replaced that. There is also a p455 or 445 forgot emissions leak or says check gas cap my main concern is getting the full horsepower back. I am thinking maybe a coil pack. Maybe cleaning the throddle body I have cleaner have not cleaner. I have also put fuel injection cleaner too not luck or change. I have not tested the fuel pressure yet, maybe fuel filter or I don't think it's showing symptoms of fuel pump but idles fine and steady let me. Know What you think
Update, well fuel filter is in the tank with the fuel pump so don't think it's that. Replaced the purge valve, the check gas cap signal not been coming up, bought one coil pack tried switching out the new coil pack with the old ones, one at a time and after clearing the codes, still no luck, hesitation, car running pretty poorly now, even with these new plugs, it's like the problem slowly getting worse, air filter and that area is air right. If I. Floor it, just wasting gas, no. Power at that rpm level. No check engine light right now after clearing the code 300, if I. Floor it engine light will flash sometimes and then usually the check engine light will come up and stay on. Possibly a catalyst converter going bad, watch's some videos maybe I. Can loosen it or clean it and test out, also check the fuel injectors doing the screwdriver test noise at idle speed seems ok but not while reviving. Idle and starts ups are smooth and ok.