How to program the LORA E5 dev board without losing AT command ability

Hi, I am using the LORA E5 dev board for LORA communications, here are some of my queries:
1.The website https://wiki.seeedstudio.com/LoRa_E5_mini/#21-erase-factory-at-firmware mentions that the AT command ability will be lost if we program it with STM Programmer. How to avoid it?
2. The specifications of the dev board itself has not been provided and just the datasheet of the module mounted on it wont be of any use. Where can we get the specification sheet?
3. Can you help me with some tutorial on programming this board without STLINK and using the STM32 CUBE IDE? I don’t have stlink and want to load and run my program on the dev board directly.