Dentist said my 2nd premolar must hev rct instead of extraction coz of sinus approximation.but i don't hev budget.is extraction not really possible?

Dental care: There are always alternative treatment choices, although they may not be as good. Maintaining tooth root with root canal treatment and crown usually better than extraction/implant/crown. Extraction alone is not advisable. Talk to your Dentist about payment plans. Seek treatment at a clinic or Dental School. But best choice is probably to work with yourDentist.