When i try using Nvidia GPU to reboot into Nvidia KDE Desktop Manager it boots me into TTY1 but from there i had exhausted all my google search for 3 days trying to find an answer to how to boot to KDM (KDE Desktop Manger) from console, i just cant find any answers using GOOGLE

could someone help me with command lines or how to fix it so i could boot into desktop manger with Nvidia graphics card? I am using Nvidia RTX 2080 ti video card and my mother board is Gigabyte Z390 Elite with latest drivers and bios.