Recommandations/troubleshooting

Work in a virtual machine

I've been into several troubles to make Odin recognize my device in Samsung's Download mode (aka "Odin mode"), until I worked in a clean Windows install in a VM (VMware Workstation Pro). As soon as you want to "play" with Android ROMs, you will need to install and try softwares and drivers from different sources.

If not for security, just keep your (host) system clean from them and work with a fresh Windows setup in a sandbox VM. This will eventually save you from fighting hours into painful drivers problems. Just do a VM snapshot before installing anything, then roll back when you are done with the phone.

Cables and USB ports

Using third-party USB cables can keep your device unrecognized from your desktop. If you can't get the phone to communicate (file transfert) with Windows, you may want to try another USB ports, then try another cables. Usually the stock one will work great.

Backup

Backup all your files, photos, videos, contacts, apps, conversations, etc before doing anything on your phone.

Do not forget that Samsung SmartSwitch backups are encrypted and cannot be read by another OS than Samsung's Android OneUI !

If you are installing a custom OS from stock, I strongly recommand to manually backup things and export contacts in a .vcf file.

Step 1 - Prerequisites

Bootloader unlocked
USB Debugging enabled

Download tools, drivers, ROM :

Install adb drivers
Unzip abd tools somewhere : https://dl.google.com/android/repository/platform-tools-latest-windows.zip
Install Samsung USB driver for Windows : https://developer.samsung.com/android-usb-driver
Install Odin Samsung ROM flashing utility for Windows : https://forum.xda-developers.com/t/patched-odin-3-13-1.3762572/
Install 7zip https://www.7-zip.org
Download latest Lineage OS ROM (.zip file) and recovery image (.img file) Vanilla https://download.lineageos.org/beyond0lte or with pre-patched microG https://download.lineage.microg.org/beyond0lte

Step 2 - Flashing Recovery with Odin

Rename the recovery img to recovery.img.
With 7zip, add recovery.img to a .tar archive (no compression) and name it recovery.tar.
Turn off the phone and remove the USB cable from the phone.
Keep both Volume DOWN + Bixby buttons pressed, and then, connect the USB cable to the phone (wired to the PC on the other side).
Wait ~5 seconds, the Download mode (green screen) should start. If you see any blinking charge icon, you failed : retry.
In Download mode first screen, press Volume UP to continue.
The device should be detected by Odin.
In Odin, select the recovery.tar file in the AP slot, and run.
The phone will reboot. Immediately hold the Volume UP + Bixby + Power buttons to enter the newly flashed Lineage Recovery.

Step 3 - Sideload LineageOS

In Lineage Recovery, go to Apply Update > Apply from ADB.
On your PC, open a Powershell terminal where adb.exe is located.
Sideload the ROM zip :

PS C:\Users\User\Desktop\adb> .\adb.exe sideload ..\lineage-20.0-20230502-microG-beyond0lte.zip
serving: '..\lineage-20.0-20230502-microG-beyond0lte.zip'  (~1%)

Wait until the sideload is done (~5 min). The phone will reboot automatically.
Configure your phone and enjoy a de-googled Android experience.