TF-Mini S lidar not sending any serial data
If you have an Arduino Uno,as shown in the diagram,  there is only one serial port, at pins 0 and 1, and they're the same as the serial communication with your PC, so they will interfere with each other.
Source: https://www.arduino.cc/reference/en/language/functions/communication/serial/
I suggest that you either get an Arduino with more serial ports (Easiest and best option), or not have any communication with the computer. The latter would make debugging harder, and you'll have to find a way to display the LiDAR data from the Arduino, without using the Serial Monitor.
Another option might be to use software serial, but I don't know how well it works, and it might be too slow for the LiDAR application.