What should I do about a dead toe nail it hasn't looked normal in 3 years.... The nail is white and looks dead or taken over by some kind of bacteria.

A . A toenail that is white and thickened could easily be a fungal infection. You might want to hve it checked out byyour physician or a podiatrist. You do have options on how to take care of it these days.
Have it evaluate. Some causes of abnormal nail growth include trauma, infection, side effects of medication, and possible systemic diseases such as psoriasis. Have them inspected by a professional to determine the cause of the problem, as treatment varies depending on the diagnosis.