Bought a car which is in poor condition.

Bought a car last September 2019 , VW polo 2019 model Within a month a car was looses power, reported to them they said I should take to any VW, only to find the car doesn’t have warranty, the car is releasing black smoke through exhaust, starring rack is noisy and all four injectors are over fueling . VW said the car is in poor condition warranty doesn’t cover and the car was involved in a car accident which is not. Went to the Garage they refused to fix it after I asked about a spare key which they never gave me, I’ve been asking for it they offered to pay half price . Also asked about road worth , the salesman didn’t know anything about it.