usually you can drive most normal cars but if you go to a high performance car garage you may find you have to be 25. I went to test drive an evo last year when I was 24 and I had to get my dad to drive it as the garages insurance wouldnt touch anyone under 25 as they had skylines supras etc..

Normal car like a zetec s you should be fine.

They rust quite badly as ford do very little in the way of rust prevention when theyre built.