I'm experiencing the same thing on MacOS with VSCode 1.58.2 and vscode-arduino 0.4.3. This was working very recently (like maybe a week or two ago) but all of a sudden it's not working today. I can ...

I want to know if Serial Monitor start first then secondly the sketch, in such a case why serial communication does not start/work ? (although the sketch is running well e.g. WiFi connection is ...

An Arduino Uno provides the processing power and drives the serial monitor. A joystick and a Hitachi H48C accelerometer are mounted on a breadboard and wired to the Uno.