Not quite. There is more than one British accent. Pronouncing the R at the end of a word is called rhoticity. Most British accents are non-rhotic, although there are some well-known rhotic ones such as Scottish, Welsh, and Irish. Most non-native speakers of English have a non-rhotic accent. It's just really hard to master that R. It's normally just replaced in a similar sound combination in their native tongues.
I wasn't referring to rhoticity anyway. As a test, say "rare." Notice the positioning of your tongue. It curls and almost touches the top of your mouth. The German R is produced from the uvula, that thing that hangs in the back of your mouth.