I read a lot about queens going missing or swarming to leave the hive queenless so my question is....can a nest ever become bee less or will queens always be produced by the remaining bees?? It seems if the queen is lost the bees just replace her
Marc, while waiting for an intro course, etc, I'd suggest you get hold of a couple of books, so you can start some studying.
Check your local library (and its affiliates, mine can get books from any other in the County system for a few pence fee).
The Haynes manual is a keeper. Honeybee Democracy is an interesting read and has an intro that should fill in some gaps in basic understanding.
Queen Cells need to be started on eggs laid by a Queen within the last week (by the end of the week, the worker larvae are too old to be 'converted' into Qs).
No eggs recently, no possibility of making a new Q.
The timings for brood development are important learning for the novice beekeeper!
There is a real risk to the colony if new Q fails to return from her mating flight.
That said, most managed colonies that end up hopelessly Queenless, do so because of misguided beekeeper intervention, particularly thoughtlessly knocking down all Queen Cells on sight.