syncing user data to username/password accounts

I'm working on a new app where I would like to have users be able to register using an email address and password combination. I would like to be able to store a data structure on the authentication server. Up until now, I've always just created a PHP interface to a custom SQL database I would write. I'd like to move away from managing my own server for this project for various reason, and was looking into amazon web services and google cloud storage. There are quite a few options and approaches. Can someone that is familiar with cloud server technologies point out to me what the easiest route to achieve what I want is for each of the mentioned platforms, or others that I haven't? From my initial reading, Cognito seems to be what I'm looking for, but I haven't been able to nail down the proper setup for Developer authenticated users. All suggestions are welcome. Thanks.