this is my controller and test case i have marked the parts that are not covered in red please help cover them

controller

public class WoW_ManageListController 
{
 public List<FulfillWrapper> wrappers {get; set;}
 public static Integer toDelIdent {get; set;}
 public static Integer addCount {get; set;}
 private Integer nextIdent=0;
 public Invoice__c INC {get;set;}
 
 public Decimal INVLICOUNT{get;set;}  
 public WoW_ManageListController ()
 {
 
 INC = [select id,Dev_Line_Item_Count__c from Invoice__c where id=:Apexpages.currentpage().getparameters().get('id')];
 
 
 INVLICOUNT = INC.Dev_Line_Item_Count__c ;
 system.debug('**********'+INC.id);
  wrappers=new List<FulfillWrapper>();
  for (Integer idx=0; idx<INVLICOUNT ; idx++)
  {
   wrappers.add(new FulfillWrapper(nextIdent++));
  }
 }
  
 public void delWrapper()
 {
  Integer toDelPos=-1;
  for (Integer idx=0; idx<wrappers.size(); idx++)
  {
   if (wrappers[idx].ident==toDelIdent)
   {
    toDelPos=idx;
   }
  }
   
  if (-1!=toDelPos)
  {
   wrappers.remove(toDelPos);
  }
 }
  
 public void addRows()
 {
  for (Integer idx=0; idx<addCount; idx++)
  {
   wrappers.add(new FulfillWrapper(nextIdent++));
  }
 }
  
 public PageReference save()
 {
  List<Fulfillement__c> accs=new List<Fulfillement__c>();
  for (FulfillWrapper wrap : wrappers)
  {
   accs.add(wrap.acc);
  }
  try
  {
  insert accs;
     }
      catch(dmlexception e)
  {
 // ApexPages.addMessage(new ApexPages.message(ApexPages.severity.ERROR,'Oops An Error Occured!'));
return null;
  
  }
//  return new PageReference('/' + Schema.getGlobalDescribe().get('Invoice__c').getDescribe().getKeyPrefix() + '/o');

return  new PageReference('/' + INC.id); 
 }
 
  
 public class FulfillWrapper
 {
  public Fulfillement__c acc {get; private set;}
  public Integer ident {get; private set;}
  public list<Invoice_line_item__c> INVLI {get;set;} 
  public integer countinvli {get;set;}
  public Invoice__c INC {get;set;}
  
  public FulfillWrapper(Integer inIdent)
  {
  INC = [select id,Dev_Line_Item_Count__c from Invoice__c where id=:Apexpages.currentpage().getparameters().get('id')];
  INVLI = [select id,item__c,Item__r.Type__c,quantity__c,Invoice_Number__c,Qty_fulfilled__c,warehouse__c from invoice_line_item__c where Invoice_Number__c=:INC.id AND Dev_Qty_to_be_Fulfilled__c >0 ];
  countinvli = INVLI.size();
  ident=inIdent;
  
  acc=new Fulfillement__c(Item__c = INVLI[ident].item__c,Invoice_Line_Item__c=INVLI[ident].id,Invoice__c=INVLI[ident].Invoice_Number__c,qty_out__c = (INVLI[ident].Quantity__c-INVLI[ident].Qty_fulfilled__c),warehouse__c=INVLI[ident].warehouse__c,date__c=system.today());
  }
 }
}

test cAse

@isTest
private class WoW_ManageListController_TC {
static testMethod void ManageListController() {
Invoice_Category__c ic=new Invoice_Category__c();
ic.name='sdsd';
ic.Active__c=true;
insert ic;
account a = new account();
a.name='sdds';
insert a;

branch__c b = new branch__c();
b.name='sdsd';
b.Dev_Invoice_Auto_Number__c=67;
insert b;


Invoice__c in1=new Invoice__c();
in1.Invoice_Category__c=ic.id;
//in.doctor__c=
in1.Sales_Branch__c=b.id;
in1.KPI_Branch__c=b.id;
in1.name='sdfd';
in1.Patient__c=a.id;
insert in1;

Integer toDelIdent=0;
ApexPages.currentPage().getParameters().put('id', in1.id); 
WoW_ManageListController cs = new WoW_ManageListController();  
  cs.delWrapper();
  cs.addRows();
  cs.save();
  
  }
  }