You need to consume more pulses, dals, sprouts
etc and also milk
and milk products in your daily diet
which will provide you vitamin b12. If deficiency is severe you may need to take some supplements. Once your b12 deficiency is corrected iron
absorption will improve. Iron rich foods include garden cress seeds or halim seeds, green leafy veggies etc, recommended to be consumed with vitamin c
like lemon juice, amla for better absorption.