OTA Updates via LoRa (TTN) with ESP32/ESP8266

How can I do an OTA update with node-red via LoRa (over The Things Network) with an ESP32?

This topic does not help me: Does node-red supports over the air (OTA) update?

I can already send data to the node with base64.
First the binary has to be split, so I can send via LoRa it piece by piece, but how did I do that?

Do I have to convert the binary file (Firmware image) to base64? And then send it piece by piece?

This isn’t really a Node-RED question. You’ll be better asking on a Lora forum. My understanding is that Lora would not really have enough bandwidth to handle the amount of data required for OTA via Lora