dual m.2 nvme configuration

Hello, I'm having a problem connecting m.2 disk to this UGREEN dual M.2 Enclosure. It doesn't fit, I can't make it work. I already have another Asus rog strix arion m.2 enclosure and everything is working fine , I know how to connect hardware. I tried to put inside Samsung m.2 980 pro 2TB...

I've read about setting up dual m.2 nvme slots as a RAID configuration, BUT would it be logical/foolish to use one Asus Prime H370-A M.2 NVMe slot to hold my OS (Win 10) and all my programs and the other for files? Would I be over doing this setup when the same results might have been acheived...