Im almost 9 months pregnant and I need to know if me and my babies father are not married do I have to give the baby his last name

I do not think that you must reveal the father's name. However, there is some caselaw in Arkansas that suggests that a biological father can have his child's birth certificate reflect the father's surname. If you wish to seek support of the father, you would likely be better off revealing his name to the hospital or put his name on the putative father registry.