Bali Reefs

Hi Guys, I am planning to go Bali for a week or 2. I'm still pretty much a novice and have never surfed a reef. In fact I'm pretty confident that I will wipe out on around half the waves I try to catch. Furthermore I am trying to get my turns down and might be more likely to be riding straight to shore rather than along the face. Is it safe to attempt to practice on the reefs or should I stay completely clear of them? If its safe can you advice which are less shallow?