Wasn't sure what forum to put this in so I figure support might work. When submitting a race with subraces, do the subraces go with it? Or do I have to submit them separately? 

You have to submit them separately.

What about for just private use. For example, I made a Bearfolk RACE and its two subraces: Grizzlehide & Purifier. However, now when I go to the character builder it only shows me the two subraces...it doesn't, like DnDBeyond official material show me BEARFOLK (2 subraces)...I instead see the options alongside all the other classes of Grizzlehide and Purifier.

Am I doing something wrong?

Thanks

 PS - It does work though. If I click on the Purifier for example, it lets me build a bearfolk Purifier..and the Purifier details page references back to the parent of Bearfolk. 

You're not doing anything wrong. Homebrew races currently don't populate a group listing, so you cannot put subraces into a subgroup, like you can see for official races/subraces and the homebrew subraces of official races. If you have "has subraces" selected in the core race, then in the builder you should find each subrace separately within the listing. Hopefully this will be amended in the future, but at least it's functional. :)

Thanks for the answer (and again Stormknight!).