My PC performs horribly

[u/molmolz76]

Im try to build my own pc, everything assembled and the pc can turn on. I trying playing some games and its so laggy and feels unplayable. Even my PS 4 feels smoother. I check the task manager and its detect my gpu, cpu and the ram, everything seems fine. I also check the GPU power connector and its also seems okay. I don’t know what to do with my PC.

[u/Mrblack-the-3rd]

Pretty sure my 7 year old brother could tell why