deploy to Heroku

[mrsunatullo]

There was an issue deploying your app. View the build log for details.

-----> Building on the Heroku-20 stack -----> Determining which buildpack to use for this app ! No default language could be detected for this app. HINT: This occurs when Heroku cannot detect the buildpack to use for this application automatically. See https://devcenter.heroku.com/articles/buildpacks ! Push failed

I can't deploy to heroky my project