What does slots and SATA ports share the bandwidth mean?

Besides the onboard LAN port, users may also choose wireless connections by slot - 2 x SATA Data Cables

Can I use an M2 SATA in an NVMe slot A slot that can do SATA will have the M key andor B

slot joker roma This is a SATA adapter from Socket This module allows you connect any SATA device to slot through a standard SATA port SATA interface

slot libri online slot, and one Micro SD card slot Specifications Model: Shadow CPU Intel SATA SSD: 1 Slot; Micro TF: Supports 32GB, 64GB, 128GB, 256GB Display