Conncet Bluetoth module HC-05 to Arduino Uno Using UART Usb to enter in AT command I have connected Arduino Rx(pin 0) to Bluetooth module Rx pin. Tx od Arduino to Tx of Bluetooth . I am able to send command to Bluetooth module using Serial Monitor of Arduino on my PC.

I have uploaded the empty code in Arduino.

I want to know why we connected Tx to Tx and Rx to Rx i.e one to one connection?

If I send command "AT" from my PC using serial Monitor of Arduino , How is it flowing to Bluetooth module.

Why not we connect Rx to Tx pin in AT Mode of Bluetooth module?

Pls explain using diagram.
By using SoftSerial you can connect the HC-05 module to another pin than D0 and D1. Example connect HC-05 to D2 and D3 and define SoftSerial to use D2 and D3.

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| HC-05 +---(SoftSerial)---(D2/3)+ Arduino +(D0/1)---(Serial USB)---+ PC |
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