Now that you've made contributions to your chosen project(s) and the application deadline is approaching, you need to finalize your application to the project. Go back to the application site, login with your Google account, and click "View My Applications". Finish filling out the Project Information section account, including links to your contributions and a timeline for the project that you've discussed with the project mentor. Double check the community's landing page to see if you will need to provide additional information in your application. Some organizations (like Wikimedia) may require you to submit your application publicly as well.
You'll be able to edit your application until the application deadline has passed. Using "Save" button after you initially create your application and every time you update it makes the latest version of your application visible to Outreachy mentors and coordinators. Saving your application for the first time effectively submits it. There is no specific "Submit" option.
After the application deadline, project mentors will take a couple weeks to decide who they want to accept as an intern. They will review all applications in the application system, and communicate their intern selection to Outreachy organizers. The Outreachy organizers may also need time to seek out additional funding to have organizations accept more interns. Applicants typically don't get any email from organizers at this time, since we don't have an automated way to send email confirmation of application submission yet. However, all applications in the system during the deadline will be reviewed.
After the application deadline and before the interns are announced, you are welcome to continue making contributions to the projects you applied for. We find that applicants often become passionate about their project, and get hooked on making contributions. Many applicants who are selected for internships continue working past the application deadline, although it is not required.