It might be said that life after death has nothing to do with life before death - that even if Heaven was real, that fact does not make any positive difference to my-life, here, now.
And there is validity to this statement; in the sense that mere, generic survival beyond death does not necessarily make a positive difference to mortal life.
Many/ most concepts of life after death do Not help with life-before-death.
It is the Christian Heaven specifically that enhances this mortal life.
This mortal life - taken in isolation - is invalidated by its temporary nature; such that every-thing, all that is beautiful, virtuous, true - will be lost, will be destroyed, sooner or later; indeed is always being-destroyed all-the-time.
In this mortal life, life is shot-through with death. Anything good is evanescent. The newborn baby harbours cancer cells; a youth in bloom carries the marks of degenerative change. All mortal achievement is swept away in time; memory is defective - and all memory is lost.
So; for this mortal life to have meaning and purpose entails that the afterlife be a place of 'permanence', where good lasts and is eternal, where we last and are eternal.
However; if life after death was merely a continuation of this mortal life; then that would leave all the problems of this mortal life unchanged.
After all; many people now and through history have found this mortal life to be a vale of tears, it is not uncommon for Men to wish for death. If post-mortal life is just 'more of the same' - then that does not change the nature of mortal life.
Therefore, merely adding to the duration of mortal life, forever, does not help in living here and now. Indeed, to live with such an expectation - forever - might well be seen as a curse.
On the other side; if life after death is seen as utterly, qualitatively different from this mortal life and if I my-self am utterly transformed after-death - or lost; then the afterlife has nothing to do with mortal life.
Some visions of life-after-life have exactly this quality - e.g. we will be spirits instead of having bodies; we will lose all our sense of self/ ego/ I; there will be no passions or yearnings; there will be no Time...
Therefore - if afterlife is completely distinct from thislife, then it cannot help thislife.
Indeed, if afterlife is utterly different and utterly better - then this life is rendered purposeless and meaningless - why bother with it?
A qualitatively-different and -superior afterlife abolishes the value of mortal life.
For life after mortal life to transform-for-the-better mortal life, entails that it be both an eternal prolongation of our mortal lives (or else 'we' will not be there to experience it) and 'yet' also qualitatively different-from our mortal lives (or else it will not be worth having).
For the afterlife to enhance thislife apparently requires that it be simultaneously the-same-as and different-from mortal life!
This is exactly what Jesus Christ offered Man. If you read the Fourth Gospel with this 'requirement' in mind; you can see that throughout Jesus is saying exactly this: that the life everlasting is one in which we our-selves are transformed, while still remaining our-selves; and it is one in which all good things are eternal.
The resurrected Man is still the same Man - Jesus after resurrection was still Jesus - yet he is everlasting.
But Heaven is qualitatively better than earth; as Jesus describes in many parables and stories about water, food, meat, wine, sight etc... when he makes clear that the Heavenly 'versions' of such entities are qualitatively better than on earth - enhanced and everlasting, yet in essence the same kind-of-thing.
In Heaven we are fully children of God; and, like Jesus, can participate in creation.
(Almost every miracle and parable of the Fourth Gospel is about this theme. I have found the best modern way to conceptualize this is the analogy - which is more than just an analogy - of development by continuous transformation. A child becomes an adolescent becomes an adult - both the same identity and qualitatively different; yet the transformation is achieved by continuous, incremental and quantitative changes. This is no paradox, but a simple matter of basic experience. By resurrection we are transformed from our mortal state in the same, developmental way.)
In sum; as I know from experience, the typical atheist response to Jesus's offer of life beyond death is that it 'solves nothing' - but merely kicks the ball further down the road; or else it entails abolishing me and putting somebody (some-thing) else in my place - some entity that is not me.
(It is no solution to my life for me to be abolished and replaced! Transhumanists please note...!)
But either way; how can this help me, here, now?
The atheist is correct that afterlife per se does not solve the intrinsic problems of this life; but needs to recognize that the afterlife offered by Jesus Christ is not 'mere' afterlife - but a very specific, indeed unique, afterlife.
And the afterlife offered by Jesus Does does solve the problems of mortal life, does enhance the meaning and purpose of mortal life; is positively transformative here-and-now.
Only after this is understood (and understanding the Christian afterlife is clearly very difficult for most people) can someone proceed to try and discover whether it is true; to ask whether it is a real possibility for 'me'.