We've had chickens for almost 50 years, and unlike another answer, you cannot tell if they are fertile by looking at them, unless they have already started developing and have blood vessels. The little white spot is there in fresh eggs whether or not they are fertile
There is no difference in taste or nutrition in fertile and infertile eggs, but there is a tremendous difference in taste and nutrition between the eggs your hens will produce compared to store eggs.
Just gather them fresh daily, and get them in the refrigerator. If you leave them in warm conditions for a few days they will start developing, and you don't want that to happen. It would be unpleasant when you broke them open.
But keep them cool, and you will fall in love with the wonderful taste of home produced eggs from happy hens, and they are very healthy for you, too.