Display input data in separate window
 

I am trying to set up an opening worksheet of a workbook, where the
user completes the relevant contact information for himself and then
enters the details of the customer. All the Customer information is
held in a separate worksheet, with 5 separate fields for each entry. A
customer may have more than one entry, with slight differences between
them. Is there a way having clicked into the first customer cell to
display, in a separate window, a table showing the 5 separate fields,
such that the user can click on any of the 5 fields to select the
appropriate customer entry, this then populates cells in the "opening"
worksheet ? I have seen mention of UserForms but have never used them
and don't even know if they are relevant to this requirement.

At present it is set up using Data Validation but is a bit clunky and
i'd like to improve it by enabling them to do it all in a single
selection.

Thanks for any/all suggestions
Regards
Fred