First of all, unless he's running a LAN with 10GbE, or has multiple SSD RAID pools/volumes, there's really no point. RAID'ing SSDs doesn't help with Random I/O, so it doesn't make them feel faster (get an Optane drive if he wants that, don't RAID SSDs), and the benefit of much higher sequential speeds (unless he's a "benchmark junkie") don't do much, unless you have something ELSE to transfer them to, sequentially. Like another RAID array, OR, a fast 10GbE LAN, to a NAS or SAN.
You said "simple RAID", then you said "SSD RAID". Which is it?
If he just wants a place to store files, protected by RAID-1 (mirroring), or RAID-5 (striping with parity), just buy a standalone NAS unit. (I am familiar with QNAP and Asustor, and Lenovo/EMC.) (And buy some of those 10TB EasyStore Desktop External HDDs from BestBuy.com or BestBuy on ebay, and "shuck" the drives, and install them into the NAS, and save some pretty substantial $$$.)
Edit: IOW, is this for S&Gs, or is there an actual NEED somewhere in all of this? If it's just for S&G, and learning about RAID, then ignore everything I said above, and just go for it. Intel H-series and Z-series chipsets support RAID. Lower chipsets, IIRC, do not.