If you have some files with the same structure you can use this (just modify your existing load):
for each File in filelist ('*.xlsx')
'$(File)' as FileName,
(ooxml, embedded labels, table is Sheet1);
Now you can also extract your date from the filename string '$(File)' with a string functions.
The whole path and filename with extension.
$(File) - substitutes there the value of the variable File. As it's string and can contain spaces use ''.
You can watch for variables in Debug mode (Button on top of the Stript editor).
Also you can run your script step by step.
You can also specify a directory in filelist ('SomeDir\*.xlsx').
You can use relative paths if you've used Directory; statement somwhere above (see help).