According the the Bhagavad Gita, death isn’t the loss of life, but it is the soul’s exchange of one body to it’s next. The soul is infinite and simply acquires and lets go of bodies just as we acquire clothes and let go when they’ve become worn out.
Fear of death is one of the kleshas, or obstacles of Yoga, which is resolved in the Bhagavad Gita, death really is not an issue because the essence of a being is eternal. Sadhguru stated a question that illuminates this point, that I paraphrase: when someone loses weight, have they lost part of themselves? No because they are not the body. When a tree loses its leaves it is still the same tree.
When you love someone are you in love with their body? When parents love their children and after ten years their children have completely different bodies, yet they still love them, so they must be loving something much deeper than the body.
Our thoughts and state of mind at death determines the body and the conditions of our next life, and death could arrive at any time. So, we must tend to the spirit as if today was our last. How do we know the state of mind or what we will think of at the time of our death which could happen at any moment? Look at what you fix your mind on. What are your daily and moment to moment focuses?