The motherboard supports Aura Sync which includes a Standard RGB header and an Addressable Gen 2 RGB header. You can connect RGB LED strips to the AURA RGB header and individually addressable RGB WS2812B LED strips or WS2812B based LED strips to the AURA Addressable Gen2 header. The AURA RGB header supports 5050 RGB multi-color LED strips (12V/G/R/B) with a maximum power rating of 3A (12V). The Addressable Gen2 header supports WS2812B addressable RGB LED strips (5V/Data/Ground) with a maximum power rating of 3A (5V), and can handle a combined maximum of 500 LEDs.

The motherboard has one PCIe 4.0 x16 slot for expansion cards.

Yes, the Asus ROG Strix B550-I Gaming motherboard has Intel® Wi-Fi 6 AX200 built-in, which supports 2x2 Wi-Fi 6 (802.11 a/b/g/n/ac/ax) and up to 2.4/5GHz transfer speed. It also supports Bluetooth v5.1. For more information, see page 6 of the manual.