Hello both of them look the same but they uses diferrenntly according to the context

In your example, you can use either (each achievement, every achievement) or both (each and every achievement-for emphasis). There really aren't a lot of rules for this. Each is used for people/things thought of individually. Every is for people/things thought of as a group. So it sort of depends on your mental view. Most of the time, which you use doesn't make any difference. Every problem is unique - correct Each problem is unique - correct Also, each is used when describing two things and every for describing more than two things. He wore a watch on each wrist and a ring on every finger.