Problems in input and output

I’m new to music production. It is my first time to use cubase as DAW and I have some problems in using it.
My audio interface is Steinberg UR22c. I plug my microphone to the left input with a XLR type and my guitar to the right input with a phone-typed. I connect the main output with my CR-X speaker.

  1. My speakers can output the sound in the computer such as Youtube Videos. The output format is shown as “Line(2-Steinberg UR22C)”. However, when I use the Cubase software, the output is UR22C mixed L and mixed R, which my speaker cannot output the sound.

  2. The audio activity shows my sound is recorded in my microphone. However, it doesn’t seemed that any sound is recorded after the recording.

3.Although I have plugged in my guitar, no guitar input is detected in the software.

This is my studio setup: