Donna 49 has given you perfect information.

I would add a few things:

First, Icelandair holds back connecting flights if the incoming flight is delayed. So, please do not worry about connecting time.

Second, one of the joys of arriving in Iceland and continuing to Europe is that you clear passport control in Iceland so your onward flight is a "domestic" European flight. This however does not apply to the UK as they are not part of the Schengen agreement on this. But perhaps for your next European trip !

Third, KEF is a very modern, very Scandinavian terminal. I would encourage you to go to the main building with all the stores rather than staying by your gate. We've made great purchases there.

Enjoy your flight !