Try to read again my post. Slowly.
No matter what Lineage based rom you choose, you won't be able to download Facebook app from the Playstore.
Check the attached screenshot. That's my device with Lineage OS official, latest build, without root.
SafetyNet (aka Google) checks if the device has been rooted, if the bootloader has been unlocked and other things. Magisk helps bypass SafetyNet, and when it fails due to new security messures Magisk developer updates the software and releases a new version.
Unfortunately, the guy behind Magisk will be out of business for several months for personal reasons.
Until then, we'll have to download Facebook from other sources, like apkmirror.