Well basically you've got to create a matrix, place your car model on it and when you press upkey, downkey it will move..
Something like this...
Rem Usual Settings
Sync On
Sync Rate 30
Hide mouse
Rem Change yourcar to the name of your object
Load object "yourcar.x",1
scale object 1,400,400,600
Rem Creates the matrix
Make Matrix 1,1000,1000,50,50
Rem Main loop
Do
Rem Variable for the object y angle
aY# = Object angle Y(1)
Rem Controls for your car
If Upkey()=1 then Move object 1,10
If Downkey()=1 then move object 1,-10
If Leftkey()=1 then Yrotate object 1,Wrapvalue(aY#-5)
If Rightkey()=1 then Yrotate object 1,Wrapvalue(aY#+5)
Rem get car object position and store in X# and Z#
X# = Object position x(1)
Z# = Object position z(1)
Rem get new camera position and store in cZ# and cX#
cZ# = Newzvalue(Z#,aY#-180,100)
cX# = Newxvalue(X#,aY#-180,100)
Rem position camera
Position Camera cX#,100,cZ#
Rem point the camera at the car object
Point camera X#,50,Z#
Rem Refresh Screen
Sync
Loop
