https://devcenter.heroku.com/articles/deploying-spring-boot-apps-to-heroku It seems that there are some similar methods in Qiita.
Heroku CLI is annoying! Anyway, I want to deploy quickly! Click here for those who are uncomfortable. (Spring Boot application is premised on GitHub etc.) If you set maven / gradle properly, it should be DB initialization (I have not tried it)
From the Personal Apps page, select New-> Create new app.
Enter an appropriate name in App name and click the Create app button.
Click Settings and then the Add build pack button.
Click the java icon and click the Save changes button.
Click Deploy and select the application to deploy. (Select your own repository on GitHub here) After selecting, click the connect button.
Click the Deploy Branch button.
When Deploy is complete, click the View button to open the application.