Eternal life mean life everlasting. A time when we won't have to die again but enjoy every bliss of it.
This is why Jesus Christ came for us in order to be saved from the law of death. Truly we will all die but we should be happy we will die because we will surely resurrect with Jesus Christ if we believed in Him.
One of the reason Jesus said fear not those who will kill the flesh but cannot kill the soul.
There is this TV series (Vikings). They served gods and are always happy when they are about to be sacrificed to their gods. They believe they will enjoy bliss with their god.
That's the concept of Eternal life only that we won't be sacrificed as a fool like those ones were.