Generally, no - you can't boot from a software RAID volume because the BIOS/UEFI/etc don't know anything about it. Your OS bootloader file might get striped across multiple physical drives and even if the BIOS/UEFI/etc could find the beginning of it (say if it happened to start in the expected location), it would have no idea how to find the rest.
Similar discussion here https://learn.microsoft.com/en-us/answers/questions/456820/boot-drive-included-in-storage-spaces
I think you can not include mere partitions in storage spaces pools, but you are NOT forced to dedicate full disks either.
Hope this resolves your Query !!
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