Shopify custom app next steps after deploy to heroku?

Hello!

I have been developing Shopify’s custom application for my customer.

I have deployed my app to Heroku with shopify app deploy based on the documentation https://shopify.dev/apps/tools/cli/getting-started

However, I cannot figure out what I need to do next

How could I configure the one that I’ve just deployed to Heroku in order to work with my customer’s store in Shopify ?

Thank you!