Maybe you can set the permission of the BLE characteristic in esp32-at/components/customized_partitions/raw_data/ble_data/, to make it only able to read/write when encrypted.

The default AT bin does not support BT classic, you need to clone the esp-at project and configure it according to the doc https://github.com/espressif/esp32-at/blob/master/docs/ESP32_AT_Classic_Bluetooth.md , and then compile to get a new AT bin which supports BT classic. ESP32 AT doc https://githu...

Are you using the ESP8266 RTOS SDK？ If it is, GitHub may be a better place to ask this question. https://github.com/espressif/ESP8266_RTOS_SDK/issues

Maybe you can refer to the doc esp32_at_instruction_set_and_examples Section 9.5.2 as an example.

If you bought a WROOM32 module from Espressif, the module should already have an AT firmware in it. And it will print "ready" in baud rate 115200 when power on.

RTS CTS seems to be optional. Mine only connects TX, RX, GND and it works fine. No need to connect CTS and RTS. Maybe you can have a try.

Of course, it can. Try to send the GET command that the server requires, it should work.

Maybe try SNTP to get the real time firstly, then start the SSL connection.

Maybe https://github.com/espressif/ESP8266_NONOS_SDK/issues is a better place for this question.
And for the SSL connection, maybe you can try the command AT+CIPSSLSIZE to enlarge the SSL buffer size firstly.

这里是 ESP32 的论坛哦，可能直接到 8266 GitHub 提问就行 https://github.com/espressif/ESP8266_RTOS_SDK/issues
另外，编译完成后是不是会提示烧录地址，是按照提示烧录的吗？