Confused installing GPU — my case doesn't have the screws I see in YouTube videos

Trying to install my GPU (Acer Arc B570 Nitro OC) into my case (PCZZOI P4, ATX mid-tower) and I'm stuck. Every YouTube build video I watch shows people unscrewing some screws on the back of the case near the expansion slots before sliding the GPU in, then screwing it in after. My case doesn't seem to have those screws, so I don't know how I'm supposed to get the GPU in or secure it.

Is this normal? Am I missing something obvious? First time building a PC so any help is appreciated.