Surely you have frozen shrimp that you bought in a supermarket, one of the others are loose but they look like small pebbles, you want to defrost them and you do not know how to do it. It is very simple take the shrimp and put them in a sealed or perfectly closed bag, place them in a bucket of cold water and every so often turn the bag until all are thawed.
Now if you defrosted them yourself and you did not know that you have to do it on a plate separating them and you frozen them all together as a block, it is very simple with the same container that you frozen them, take them out of the freezer and put them in the refrigerator until they thaw