Prick out, in other words plant each geranium individually in its own little pot. Be careful not to disturb the roots when you do this. All the seedlings in the pot you have photographed are leaning one way, indicating they are leaning towards the light. You either need to turn each pot but 90˚ each day or make sure the light isn't so limited. Are these indoor or outdoor geraniums?

I agree with Moon growe. Give each plant it's own pot about that size so they can reach their fullest potential. When the temperatures warm up, they should go outdoors in full sun if you want flowers.