If you are looking for free ways to see what is available, use "Open Source Intelligence" (OSINT) techniques:
Instead of "hacking" Facebook, they are installed on a target device and capture activity (messages, stories, likes) directly from the operating system.
These sites often scrape your personal information to sell to third parties. 1. Browser-Based "Viewers" (Cached Data)
Most websites claiming to offer "instant access" are designed to:
They cannot access live private posts, stories, or messages that were never made public. 2. Legitimate Monitoring for Safety