code: public void setForward(String destination) throws WorkspaceApiException {
          try {
              VoicesetforwardData forwardData = new VoicesetforwardData();
              forwardData.setForwardTo(destination);
  
              ForwardData data = new ForwardData();
              data.data(forwardData);
  
              ApiSuccessResponse response = this.voiceApi.forward(data);
              throwIfNotOk("setForward", response);
          } catch (ApiException e) {
              throw new WorkspaceApiException("setForward failed.", e);
          }
      }
docs: Set call forwarding on the current agent's DN to the specified destination.
  @param destination The number where Workspace should forward calls.