In your other thread there were some instructions for doing different methods like bluetooth from user Nemesis:
They might make more sense after practicing the basics with USB cable. mBot power must be on for computer to recognize it. Connect usb cable from mBot board to the computer
In mBlock software, choose Connect->Serial Port->COM4 or COM5 or whatever appears
The title bar in program will show 'Serial Port connected'
Choose Boards menu and select 'mBot'
The software is now set for programming the mBot controller board. You should use the Connect menu option to 'Upgrade Firmware' and also use the 'Reset Default Program' after changing the mBot program to return to basic functions like IR remote control (RC Car style)
If you have already made some program scripts, they can be run while tethered by placing at the top the Green Flag block in 'Events'. Click on that block to Start and Stop the program.
This does not require upload of the program, but will not run when disconnected.
Use either 'Green Flag' activation script to test program, or replace it with the 'mBot Program' script (in ROBOTS) to start the script for upload to the mBot.
Right click on the 'mBot Program' block and select 'Upload to Arduino'. A new window appears with text program code and a button for 'Upload to Arduino'. Once that button is clicked, the program will compile, then an Upload window will appear. When it finishes, (Program may start automatically! Be ready) turn off the mBot power switch and disconnect the USB cable.
Turn on mBot power and your program should run.
Again, be sure it is in a safe place, and good luck!