can i put my boyfriends last name on my babys birth certificate?

baby mommy šŸ’‹

okay so I'm 18 weeks pregnant , my boyfriend went to jail about 1 week ago and we just got the bad news that he will be in there for 6 months which he would get out September 2018 , im due a month before on August 27 , i was wondering if i could still put his last name when the baby is born even tho hes not there ??? I've heard you can send some paper work to him at the jail so he can fill it out and sign in there but not sure soo confused šŸ˜•