Serum folate (folic acid) 5.0 ng/ml hct 23% vitamin b12 78 pg/ml mcv 116 fl 1, what does this mean?

Low B12: And your severe anemia and very large red blood cells (high MCV) are probably the result. If you are a vegetarian, please reconsider or get with someone who can guide you about the supplements you need. If not, and you feel healthy otherwise, it's likely you have a problem absorbing vitamin B12, and will need injections frequently to fix the anemia and avoid permanent brain damage. It's serious.