Check out example codes for "c# return task list". It will help you in understanding the concepts better.

Code Example 1

private async Task<List<Item>> GetListAsync(){
  	//Create a list object and assign it to a new task
  	//which returns your list object
    List<Item> list = await Task.Run(() => manager.GetList());
  
  	return list;
  
  	//Or you may just need to await something and just return a list
	await SomeMethod();
	List<Item> list1 = new List<Item>();
 
    return list;
}

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