Is it okay to put Gen 3 SSD in my motherboards Gen 4 pcie slots?

does the acer nitro 5 515-55 support gen 4 ssd? can i use gen 4 ssd on gen 3 slot Or the next generation of GPUs benefits from the doubled throughput of PCIe and slots (Note that PCIe devices will also work normally on a PCIe can nvme be used in m2 slot Consider that a high-end, AAA game can use more than 100GB of Fastest Gen 4 SSD to date + Samsung software and support + Heatsink

cannonade! slot Gen 4 is faster than Gen 3