Thanks for asking the query,
I would suggest you to first get a clinical evaluation done by a Dentist
, take an OPG x-ray.
Infected tooth can also be root canal
treated and saved permanently.
Tooth which are mobile, root stumps are to be extracted and replaced by a fixed and removable denture.
Depending upon the x-ray tooth which can be saved can be root canal treated, and remaining can be extracted and replaced.
I suggest you to enquire for any Charitable Dental Trust or a Dental School in the nearby place where you can get your treatment done at reasonable rates or even free of cost.
Hope this helps out.