Yeah theres a lot of. Personally i use mostly
Share Your Desktop 
Nicco Loves Linux
https://www.youtube.com/channel/UCONH73CdRXUjlh3-DdLGCPw
Linux Scoop
https://www.youtube.com/channel/UCNnUnr4gwyNmzx_Bbzvt29g
or simply reddit unixporn
In my opinion, this is completely sufficient
Keep it as simple as possible. Dont use kvantum. Take the clean Plasma theme and modifie it by yourself as @z580c described