Hey there and welcome to the forum!
The entire code must be submitted. If the code submission is incomplete, you risk voiding your eligibility.
Now, other people have also asked whether or not the repo needs to be public, but in fact, you can submit the codebase privately via a .zip
file.
The bigger problem I foresee here though, is that they seem pretty explicit about developing a new project, and while I’m not sure what exactly your own project looks like and what you would do, I think it would be wise to start from scratch and not submit something you’re already working on.
This section in their rules is pretty important when considering submissions, especially like this one:
As a condition of receiving the Prize, each Confirmed Winner grants Google, its parent, affiliates, agents, and partner companies, a perpetual, irrevocable, worldwide, royalty-free, and non-exclusive license to use, translate, dub, broadcast, exploit, reproduce, adapt, modify, rearrange, add to, delete from, copy, publish, distribute, publicly perform, create a derivative work from and publicly display, in whole or in part, Your Submission, app code, and any other materials or other recordings that may be made of or by You…
Which is legalese for “You forego all rights to your project as being something separate from Google”.
If you step into this competition understanding this from the get-go, you can build accordingly. That is a choice only you can make, but hopefully this helps you make the appropriate decision for you and your project.