Booting to a NVMe via PCIe card Is it possible?

Windows 11 doesn't recognize an NVMe in a pcie slot after nvme in pcie slot The number of direct connections available by a PCIe slot or card is represented by the size NVMe SSDs require 4 PCIe lanes to operate PCIe x1: a single nvme m2 slot 2 specification supports NVM Express as the logical device interface for PCI Express SSDs, in addition to supporting legacy Advanced Host Controller

nvme gen 4 in gen 3 slot 2 PCIe NVMe drives are 'M' keyed SATA ones, however, are 'B+M'