You can find the batteries here: https://www.modalai.com/products/m10000538
Any 2S LiIon hobby charger will work. Something like this is all you need: https://www.amazon.com/ISDT-608PD-Battery-Charger-Discharger/dp/B0CM9BFQSX
Handheld transmitter depends on the configuration of the drone. You can order the drone with a pre-bound charger ready to fly from the website.
The main debugging cable is a standard USB-C cable