You cannot add "Cisco Catalyst 9300 - Network Advantage - switch - L3 - Managed - 36 x 2.5GBase-T (UPOE) + 12 x 100/1000/2.5G/5G/10G (UPOE) - rack-mountable - UPOE (490 W)" to the basket because the product is out of stock.
Cisco Catalyst WS-C3560CX-8PC-S Compact Switch – 8 POE+ Ports, IP Base Layer 3, Managed