I'm 74 year old female. do i need a multivitamin with iron or not?

Multivitamin : I would definitely start taking a multivitamin tablet. If you need iron depends if you're anemic.

Yes: It helps to take Vit D3,calcium, for bone health. Vit C for Immune health, Vit B complex especially B12 and Folate (folic acid) for Blood and cognition,Vit E for Circulation,Leg cramps . Magnesium for heart. Iron may nor be necessary if you are eating Healthy and Balanced diet. Get CBC andVitamin level checked and that will give you better perspective