What would we need in order to fix his papers and how much will it cost?

Generally, a U.S. citizen age 21 or older may sponsor a parent living abroad to obtain immigration benefits through consular processing. Significantly more information is needed in order to provide a legal analysis of eligibility for your father and to provide an estimation of the time involved for the process. It would be wise for you to consult with an immigration attorney who, after learning all of the relevant information, could advise about eligibilities, options and strategies to attain your goals, and who then could offer legal representation in the often complex application process.