Biomolecules have to be enantiomerically pure, exclusively right-handed or left-handed, to be used in living cells. Chemists can only produce mixtures of biomolecules in the lab due to all the side reactions. Then there is the half-life problem. RNA has a limited half life of a few minutes to hours or days, depending on the type. Same with other biomolecules. Stability is low outside of living cells. So how did these biomolecules miraculously come together quickly enough and in sufficient purity and chirality to make the first living cells?