Help with movement, and some other stuff

ok, i’m making this car game right. but i haven’t been able to make it move properly, only across the screen i i don’t want that, maybe a looping backround is the awnser but i havent figured that out yet. and also you can buy parts for your car right thats ok with the money and all but if i exit the buy screen go back in i have to pay for the parts i’ve buyed erlier + that if i buy a part and don’t have enough cash, i go into minus. so please help me somone, and excuse my english i’m not so good at it…
peace*##*