How to release an app to Alpha group before any release to the public (playstore)?

Question

I believe this question would be a repeat of this question:

Android in-app products not appearing in Play Store or app

but that question does not answer my question clear enough, so I'm asking again.

I have an app that I would like to test the in app payment feature, and I have read that in app products will only be available once the app has been published to at least beta or alpha.

I want to publish the app to beta or alpha, but it seems like in order to get a opt-in URL, you need at least one version of the app released to the public(playstore), if I am not wrong, and I do not want to do this as the app is still in development.

Is there a way to do a alpha testing before releasing no versions of the app to the playstore?

Here is a screen shot of my google play console:

Edited: Why am I not seeing a opt-in URL here?

Answer 1

So it turns out that it takes like 2, 3 days until the alpha or beta testing goes live. The official documentation does not say anything about it, and it actually makes it sound like it happens instantly.