So I was enlisted in the army in November but I started training in January and the question ask what was my status December 31 and the options are reserves ,active dutty ,national guard , military r

If your date of enlistment into the US Army was in November of 2019 then your status is active military on 12/31/2019.

 Your first day of active duty status was the day you went through the gates of whatever base your basic training was, and before you went to sleep that night you were thinking "OH MY GAWD! WHAT HAVE I GOT MYSELF INTO!?!" That was your first day of active duty.