Look for the Common Dialog object. For a quick test:
- Start a new project
- insert a CommonDialog and an EditBox into the layout
- make two events in the event sheet like so:
[code:8irsnubz]+ System: Start of layout
-> CommonDialog: Show open dialog
+ CommonDialog: File dialog: OK
-> EditBox: Set text to CommonDialog.FirstSelectedFile[/code:8irsnubz]
Note that you can do this without typing anything, if you haven't learned the finer points of Construct's interface. You can also do quite a bit more with this object.
Anyway, the result is a string, and can be used in any other way as such.