I am 22 yrs old planning to marry my significant other, we've been together for 6 yrs and living together for 3 yrs. He is a permanent resident here in the U.S ., and I wanted to know what is the process after we obtain our marriage license for him to become a u.s citizen?
Your question is rather unclear. If your fiance is a permanent resident ("green card" holder), he will not be required to file an adjustment of status. If he is interested in applying for U.S. citizenship through naturalization, he must establish he has maintained continuous residence in the United States for 5 years after he obtained permanent resident status. The period is reduced to 3 years if the permanent resident is in a valid marital union with a U.S. citizen for 3 years.