Model builder: Select Layer by Attributes_select subsets and export to new shapefile

Hi,
i would like to create an automated process which will import a text file in ArcMap, convert it to event layer, then select different rows at a time given the value of a field defined as group parameter and export these rows in a different shapefile.

Until now i have figured out how to import the text file and make an event layer for it, but i am stuck with the iteration for attribute selection.
It would also be great if the user could be given the option to choose which rows to be selected (i.e. the value of the group field) each time they run the model, instead of creating shapefiles for every subset. Is it also possible to name the final shapefile after the value selected for the group field in an automated way? Or if not, is it possible to give the user this opportunity (i.e. by clicking Run Entire Model, a window appears asking them to enter first the value of the group field and then the name of the output shapefile)?

Thanks in advance for your help!