Mimicking a file upload

I have an excel sheet that has a ton of info and what I'm trying to do is mimic a file upload on my seeder so that my other functions will then do what they need to do.

So it's kind of doing what the UI would be doing but this is in the seeder. I'm not sure how I would go about doing it.

This is the only thing I have in my seeder

$file = storage_path('test-folder/TEST EXCEL SHEET.xlsx');