。
She doesn't know how to drive a car.
Literal
She [topic-は] car [of-の] driving [of-の] way [subject-が] does-not-understand.
~のしかた (how to do X) is a pattern for expressing method: 運転のしかた = 'the way of driving.' わかりません (doesn't understand/know) is the polite negative. The double の chain (車の運転のしかた) builds from car → driving → method. しかた (仕方) literally means 'way of doing' and is extremely versatile: 食べ方, 使い方, やり方.