well of eternal life

If you mean how to keep your skin young then the secret is not to drink or smoke and to drink plenty of water and use a good moisturiser. If you mean how to keep yourself youthful then the secret is to be happy, active, relaxed, don't hold grudges and be thankful for everything you have, eat well and sleep well and try new hobbies and make new friends often. Worry less and love more. Also take a good multi vitamin.