In a singles lawn bowling game how many points do you need to win?

It depends on how the heads up scoring is setup. If you are just bowling heads up, then total pin count is all that is important, this would be scratch. If you are bowling with handicap, you take the total scratch pin count and add handicap, the higher score wins. If you are bowling in the Peterson System, with a per game point system, then the person with the most points at the end would be the victor.