dtoverlay=pi3-disable-bt

: Provides various driver packages, such as the WLan Driver 802.11n Rel. 4.80.28.7.zip, which is highly compatible with older Broadcom and Ralink-based USB hardware.

Find the "Unknown Device" or "802.11n WLAN," right-click it, and select Properties tab and select Hardware Ids from the dropdown. Look for strings like VID_148F&PID_3070 (Ralink) or (Realtek) to confirm the manufacturer.

This is an dongle. Do not expect Wi-Fi 6 speeds.