How to unistall open core, reinstall original os and keep my files on imac late 2015?

Hi,

Hope someone can help me. I have an imac 5k late 2015 that I installed OpenCore on sometime this winter and updated to Sequia.

It's buggy and laggy and now it doesn't really wotk with my photo software (glitches etc) so I want to uninstall it, revert to the newest os my imac supports and crucially keep my files, programs and settings.

All my files are on external harddrives so those are okay (they're also backed up on Time Machine), but how to I keep my files and setting on the Mac drive? Those are also backed up to Time Machine, is it possible to restore those with every setting in programs etc in place or do I have to start over?

Is there as step by step guide somewhere?

Author: @nordvest2