The getting started guide for Deployment Manager makes an assumption that you already have an application deployed to each of your environments, and it needs to be updated to be built on PegaDevOps foundation. However, if you are deploying a brand new application it is not necessary to manually import it to each environment. Deployment Manager will handle migrating the new application. We call this a "First time deployment".
As long as your application is built on PegaDevOps foundation in the development/SoR environment, and the application's access group does not exist in the target candidate environment the Application RAP will be deployed, and the pipeline will progress successfully.
If the application and access group already exist on the candidate environment, but the application is not built on PegaDevOpsFoundation then you can expect to see an error during deployment.
Also, when creating a new application make sure you are familiar with the recomended structure outlined here.