10 public limit users on free plan

[Jeff_Hager]

How to create a login option inside a public access app?

That’s because you are in the builder and already signed in. The experience is different with the published app. No. Not without making your app completely unsecure and losing the ability to use user profiles, row owners, and to some extent user specific columns. I would not recommend it. If you need more users, then use a different plan.