How to extract lines from sheet to another and delete them from the first one
 

I have a 1000 lines text document with first and last names.one per line.

Using a script I extracted 300 lines with specific names from that text document and exported to a new text document.

Now I need to delete this 300 lines from the original file but I can't because there are randomized and I can't do it manually.

Can excel help me with this ? if yes, how ?
thank you