You can live life only in the present moment. The desire to live forever is a desire born out of your inability to squeeze each present moment of all its gifts.
Its a desire borne out of your constant postponement of the present for some distant goal.
Unless you start living intensely in the here and now no matter what you have or do or become, you will keep feeling a constant hankering for more.
Live life as intensely each moment not unlike a Yoga session in which you have given your all.