Can I Use a PCIe NVMe SSD in a PCIe Motherboard Slot?

I'm trying my first build and I bought a samsung 980 PCIe NVMe SSD which is a PCIe Gen x4, NVMe interface

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genting slot BUT you go buy the off brand no name cheaper 1TB Gen 4 NVME for lets say, 70$ (6-7K read

genie jackpots megaways slot 2 NVMe SSDs are backward-compatible, so even with a Gen3 platform, you usually get better value from a Gen4 SSD even if it can't run at its rated speed