for Samsung Galaxy A50:

Force Restart: Power + Vol Down Button
Recovery Mode: Power + Vol Up Button
Download Mode: Vol Buttons + USB Plug In

Flash:
- (if format everything) Wipe - Format
- Wipe - Advance - Dalvik, Cache, System
- Install/Flash - <IMAGE/OS/KERNEL> - Flash

GApps:
- Wipe - Advance - System - Repair/Change FS - Resize
- Mount - System, Vendor
- Install/Flash - <GAPPS/ADDONS>

WARNING: DO NOT UPDATE MAGISK IN ANY WAY

REGISTRY => https://www.google.com/android/uncertified
GAPPS => https://sourceforge.net/projects/nikgapps/files/Releases
ROM => https://xdaforums.com/t/rom-13-0-unofficial-lineageos-20-for-galaxy-a50.4589679