Hi,
Sorry, there is no such feature at the moment because HivePress implements the directory/marketplace features only, blogging features are related to WordPress itself. Please check if there is some plugin for the front-end post submission, or you can use some advanced contact form plugin to accept post submissions from authors via a separate page, and then you can moderate the submitted content and publish it.
Some of our users tried WPForms, and it worked for them, you can check it on your own.
Please ensure that you set up the social methods correctly, you can check this doc How to enable login methods - HivePress Help Center.
Regarding the email, please check the solution in this topic Change email name sender (you can also check this doc How to set up emails - HivePress Help Center).
P.S. If you purchased a theme or extension, please enter the license key in the forum profile settings, this will enable the Premium Support badge and ensure a 24-hour turnaround time.