Log in to your Azure Account, if you don't have one read this article and create Azure AD B2C as described here.
Click on All resources and find your Azure AD B2C tenant and click on it.
Click on Azure AD B2C Settings
Choose your account and click on Azure AD B2C Settings.
Click on Identity providers
Click on Add
We are choosing Google as Identity provider
And now we have to registry our app in the google console to get Client ID and Client secret
Read this blog post how to do it.
Paste Client ID and Client secret and click OK and then Create.
Now we have got Google as Identity provider
Now we have to define User flows. I am going to follow this microsoft tutorial.
Click on User attributes
Click on New user flow
Choose Sign up and sign in flow
Spesify Name, choose Google and Email signup. We are not going to activate multifactor authentication.
Click on Show more and choose following attributes. This is just example, you can choose here what you want.
Click Create.
Links in this blog
Create Azure Active Directory(AD) B2C