It is impossible to assess the odds unless the exact rules are known.

If the host knows where the car is and the other two doors hide both hide goats, you only ever get the choice of a car or a goat. Your first choice has no meaningful effect unless you are particular about which goat you get. The only 'unknown' involved is which goat may be eliminated, he will always eliminate one. Your choice is always 50/50 between a car or a goat.

If the two 'other' prizes are of different values and he always eliminates the lesser remaining prize depending on your first choice, your second round strategy should be dependent on the outcome of the first round, so could be better than 50/50 in the second round.

If he doesn't know where the car is in either of the above cases, it becomes a totally different game. Your odds of winning a car will be zero if he's randomly chosen that door. So your odds are less than 50/50.