Gen 2:8 And the LORD God planted a garden eastward in Eden; and there he put the man whom he had formed.
Eden is an area, the Garden was in Eden, but all of Eden was not the garden.
This is an interesting quote from a Bible Study on Genesis
In the east part of a territory called Eden, God planted a garden. God created Adam outside of the garden (but in Eden) and then put him in the garden. In other words, God created the garden before He created man—just as He created conditions before the fish, beasts, etc., came forth. First, God created the environment, then the beings. Incidentally, Eden means “pleasure,” “delight.” Adam’s creation was a delight to God and to man.
Adam saw something of the unfinished earth before he was put in the garden, unless he was instantly zipped over there. If we have the right heart condition, it is sometimes good for us to have a contrast—to be poor and then rich, for example, or to have suffering and then relief. The contrast helps us to be content with our surroundings, to appreciate health, etc. Adam would have been translated into the garden, just as Enoch and Elijah were many years later. While in the garden, Adam could not see out of it because of the terrain.