I took my car to auto part store to have them test it. The check engine light was on and car was running bareally bad. They gave me a obdcode to look up. It said P0302

They could have told you there. Covers a lot of things.
P0302 - OBD-II Trouble Code

I'd start by checking the spark plugs, particularly on cylinder 2. If they have not been replaced in the last 30,000 miles, consider getting it done. Ensure the spark plug wires are in good shape. If one plug or wire is bad on a 4-cylinder engine, it can make a big difference.