Q: HELP!

One random day my Kia started losing power while driving it, My check engine light came on, so I went to get the trouble code. The code came back as P0305. I drove it 2 more weeks (waiting for pay day to take it to a mechanic). It didn't hold up for me to get it there. I began to smell a burnt rubber smell while waiting in the drivethru. Suddenly I seen a little bit of white smoke, I couldn't tell if it were me so I turned my car off. When I went to start the car again it gave me trouble. I was able to pull up to get my food once I started driving down the street it started to shake a tad and all of a sudden it stopped. I tried to crank again and nothing. At this point the lights were no longer coming on so I attempted to get a boost and nothing happened. I ended up purchasing a new battery and when I turn the key all the lights go dim. We checked the started and it's good. I really need help.

My car has 160000 miles.
My car has an automatic transmission.