Note regarding the ID: The numeric ID 4120005 typically refers to a very old version of Facebook (around version 3.7 - 3.9) designed for Android 4.0 - 4.3. These versions are extremely old (circa 2013-2014) and will not work on modern Android phones today, as Facebook has changed their server protocols significantly.
Here’s a well-written, positive review you can use for Facebook’s older version APK (e.g., version 4120005) on Android: facebook 4120005 apk older versions for and work
Installing an older APK requires a few extra steps to prevent the Android system from blocking the installation or immediately forcing an update. How to revert Facebook to previous version? Note regarding the ID: The numeric ID 4120005
Step 5: Install and Disable Auto-Update