I’ve been doing this with Excel’s built-in “Protect Workbook” feature
just go to File → Info → Protect Workbook → Encrypt with Password. Super simple, and it locks the file instantly. Make sure you remember the password, because there’s no recovery.
From what I’ve done, you can search Google like this: site:instagram.com username keyword. It’ll pull public posts with that keyword from that account. Works best for accounts that aren’t private.