It seems to have 2x M.2 ports.
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1 x M.2 Socket 3, with M key, type 2242/2260/2280/22110 storage devices support (SATA & PCIE 3.0 x 4 mode)*5
1 x M.2 Socket 3, with M key, type 2242/2260/2280/22110 storage devices support (SATA & PCIE 3.0 x 2 mode)*6
But one of them is only PCIe 4.0 x2. So any current M.2 drive will be significantly "slower".
But you could add several SATA III SSDs. Depending on what you use it for, you'd never notice the difference.