Send bin file over BLE

I want to try implementing a BLE firmware over-the-air update on an embedded device. I have the firmware ready to test, but I need to figure out how I can send a file over BLE from a Thunkable app. I just need to know how to take a file from my phone and have it sent out over BLE in packets of 512 bytes. Is this possible with Thunkable? I can’t find any way to add and interact with a binary file.