Question: How can snakes talk?
Answer: This question is addressed in Genesis for Ordinary People.
However, we can say here that the garden of Eden scenario ought to be read with a discerning mind. Adam named the living creatures that were in his vicinity. The Hebrew word used for “creature” is “nephesh,” which means “soul,” or “living being,” or “life,” or “self,” or “person.” Therefore the naming of the creatures could include creatures who have spirit attached to them, such as angels who were on earth at that time. After all the serpent, that Genesis talks about, is an animal but we also understand that this particular creature was a guardian cherub too.
Figurines have been found in southern Mesopotamia that have humanoid bodies and reptilian heads. (A quick internet search will show you photos of them. Search for “Ubaid Figurines”.) As Bible students we ought not to be quick to dismiss these figurines. The local Ubaid people in 5000 BC had their own way of relating their story of the serpent. Ningishzida was a guardian. His name in Sumerian is translated as “lord of the good tree”. Ningishzida is depicted as a serpent. In 2 Kings 18:4 we read that Hezekiah broke up the bronze serpent that Moses had made, because the people of Israel had been offering sacrifices to it. They called the bronze serpent Nehushtan.
Furthermore, we read (just after the creatures were named by Adam) “for Adam, no suitable helper was found”. That statement informs us that Adam was looking out for a spouse. He wasn’t looking for a mate among eagles, cows or snakes, we see something further. Archaeology has informed us that once water came to the southern Mesopotamian area, people quickly followed - about 5500 BC. The first society to settle in the area was people who shared a common way of life, known as the Ubaid Culture.
If Adam was going to live until he was 930 years old he needed a wife who would also live that long. If Adam married one of the local Ubaidian women he would have to marry about 11 times, presuming the Ubaidian women lived to be an average of 75 years old.