how do i get same result like all archiviz videos on youtube has??

I have been trying to get same archiviz result like on many videos on youtube. i have been asking for help and got information and followed all instruction in order to get the result but it ends up in a boring unrealistic graphic with bad shadows, bad lightning. i never got the result i want! how are they doing that??? can somene please help me i beg you guys for help.

An update! unreal engine 4.26 solved all my problem with lightning & I got the result I wanted. The only problem now is there seems to be a bug in the RHI settings. when I have dx12 RHI enabled an error comes up after a few minutes of work that closes the unreal engine and a message comes up that says my GPU has crashed or been disconnected. My Gpu supports DXR & when I have the same settings in unreal editor 4.25.4 with the older GPU light mass it runs without any problems.