In your own module add an entity (extraInfo) with the additional attributes you like to store.
Make sure there is a 1-1 relation between account and the created entity.
Create the account in the administration module in the microflow and a new object in the extra info entity, make sure to set the association between the account and the extraInfo object when creating the object.
Create a page showing the data for the acocunt in a dataview, nest a second dataview in the account dataview which shows the extraInfo object over association and open this page from the microflow and you should be good to go.
To find out more on how Mendix works I suggest to work through some of the learning paths that can be found here: https://academy.mendix.com/link/paths