Before shrimps are let into their new environment they need to undergo acclimatization.
It is a process during which they adapt to different temperature and chemical composition of water. Shrimps need to be unpacked from a plastic bag and poured into a clean bowl /container. You have to make sure that nothing is left in the bag.
Next, using a small diameter tube or some container, you need to add water from your aquarium. It has to be done gradually so that the whole process lasts about 30 minutes. The amount of water you add should be similar to the amount of water in which your shrimps were transported.
We can shorten this process if you are sure that the water parameters (in both environments) are similar.
Wait for some time if there is a big difference in temperature between the water in bag and in aquarium.