How do I use chmod on a Mac to make new files inherit parent directory permissions?

On **MacOS**. I want to make it so that any new files/folders that get created within a specific folder have the same permissions (**not** _group_, that's already taken care of) as those of the parent directory. On **Linux**, I would normally use setfacl, but it looks like chmod on MacOS might be able to do what I'm looking for. I've read through the man page for chmod but I still can't figure out how to properly format the command to get what I want.