linking older threads is not intended t imply that the question has been answered to its fullest extent or that new answers are discouraged. But the OP may be interested in reading the threads below:
u/XenophonTheAthenian on How were Atheists treated by Greek / Romans?
u/i-ate-a-penguin on Were there atheists or agnostics in the Ancient world? What did they believe and how were they treated?