I'm new here, and I see a lot of races are not even added yet, Apex Predator for example. So how does one add it?

It would have to be added by us, that being the moderators. Currently, we do not track online only races, but we will consider adding them post-Volume 9.

Thanks :)

it's post volume 9 and no more updates are coming. can we start adding online races in?

They will be added at some point after New Years.