I am flying to Dublin to Stockholm, with a transfer in Oslo, this is my first time on a non-direct flight. There is only an hour layover between the flights, is this enough time? Do I have to go through security in Oslo airport?
If they are on the same ticket (not self-transfer), should you miss the second flight due to no fault of your own, then the airline has to get you to your destination. If it's self-transfer, then you're on your own, and the Stockholm-Oslo return flight will probably be cancelled as well.
As both Norway and Sweden are Schengen countries, you will clear Schengen immigration in Oslo. If you are travelling on an Irish passport, then this is a formality, and shouldn't take long