Is calcium and vitamin d 3 good for skin and eczema?

i have been drinking 2 litres of water a day and my skin is spotty i then reduced it to 1 litre a day it seems to have got worse i have now stopped drinking it and have 3 gles a day,also i suffer from eczema i had cancer 6 years ago also had a full hysterectomy so going through menopause lacking calcium and vitamin d would they do my skin any good if not please can you suggest any thing that would help in everything ie skin thanks hayley