Did you assign your modes in Betaflight? Flipping your arming switch results in the little yellow marker jumping to the selected range? If not, go set up your mixes on your remote to assign your arm switch to a channel. Then select that channel in betaflight for the arming mode and select a range.
If that part already works, there should be some warning flags indicated in your goggles or when plugging it into betaflight and trying to arm. Let us know what these flags are.
Let's take flight together and elevate the world of FPV drones to new heights.