You have opened a hive and found queen cells. First of all, don’t panic and, whatever you do, on NO account adopt the Dalek strategy of ‘exterminate them, exterminate them’! It did not work for the Daleks - they lost out to Dr Who every time - and it will not work for you. Destroying queen cells to prevent swarming never has been and never will be a successful method of swarm control. If you destroy one lot of queen cells the bees will immediately make some more and will probably swarm earlier than normal in their development - often before the first cells are sealed. If you destroy queen cells twice you run the risk of the colony swarming and leaving behind no provision for a new queen.