Any symptom? There is nothing such that you can extract vit b12 You will have to include it in your diet Kindly detail about your diet i will explain what to incorporate

Vitamin B-12 can be found naturally in animal products, such as fish, meat, eggs, and dairy products. It does not typically occur in plant foods. Good dietary sources of vitamin B-12 include: beef pork ham poultry lamb fish, especially haddock and tuna dairy products, such as milk, cheese, and yogurt some nutritional yeast products eggs