i need some goldfish help

i got 4 small common goldfish at walmart and a pet carrier to put them in it has some hols at the top too and the next day they all died so i got some new ones and one of them died i give them 2 pelets 3 time a day am i over feeding them or are they not getting enough of air what should i do to keep them from dying or what am i doing wrong plz help me or is it the way walmart takes care of them should i go some place else and get them plz help

Your tank needs time to develop the beneficial bacteria necessary to convert fish waste into harmless nitrates. Leave the tank set up for a week before adding the fish. You Also should have gravel to increase the surface area of where it is growing. You will need to change half of the water every week, Then night before, set some water out (the chlorine will evaporate), then pour half of the water into a container with the goldfish in ti. Swirl the remaining water around to suspend the particles and dump it out. Don't worry if there is still some stuff left in the water, you need to keep feeding the bacteria and a tank that is too clean is just as bad as a tank that is too dirty. Refill the tank with the old water that you saved, the goldfish and the new water you set aside the night before. For the first week that you have the goldfish feed them only two bits each once a day, then twice a day for the second week, then three times a day from the third week on. This will relieve some of the stress of your tank being new and it will not harm the fish to be on a short term diet.