Is 3 Hours enough for my next flight ?

I'm traveling to Moscow at 5.35 am. May 9 2017. S7 is my airline. from Beijing To Moscow.Actually My Flight from Bangkok arrive to BJ International airport at terminal 2 on 1.05 am. Air asia is my airline then I need to go to Terminal 3 I have 3 hours approximately. Is that enough time for transfer procedure ? And More question how to go to Terminal 3 from Terminal 2