Issues with the TX pins for recieving data from the HM19 and HC05

I bought a hm19 (link 2), 2 hc05s, an Arduino micro, and an Arduino due. I'm trying to turn an led on and off using my phone over Bluetooth. I verified that all modules work by themselves. So here's my issue.

First is that the Hc05 (link 1 below) modules simply do not respond to any AT command at all but work for serial communication. I have tried shorting a pin to send it into AT mode but that just made it impossible for me to communicate with it since I cannot get any input on my desktop using an USB cable from the Bluetooth module which brings me to the second issue.

Second is that I can send inputs from the serial monitor from my desktop to my phone but i cannot send data from my phone to my desktop. I have tracked this issue down to being in between the Bluetooth module and the Arduino. I have strong reasons to believe that DSD tech (hm19) have mislabled their bluetooth module because plugging rx into rx, tx to tx, gnd to gnd, and vcc to 5v works while flipping the rx and tx pins gives me a weird format.

Is there anyway I can fix the second issue preferably so i can diagnose the first one myself

Link 1:
Link 2:

Connecting RX to TX and TX to RX

Connecting RX to RX and TX to TX responds with only the intended single line of "1"

All inputs were "1" and were sent from my desktop to my phone
here's the code

char inputByte;
void setup() {


void loop() {
  if (inputByte=='Z'){
  else if (inputByte=='z'){

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