Choose Program Real Microcontroller from the Start part's menu (by right-clicking on the part). This opens a window that will let you start to transfer the program to a suitable programmer connected via the serial port.
If your flowchart uses variables, move your mouse over the Start part and click on the button displayed. This opens a small editor showing the names and ranges of each variable. For each variable you can change the range between 0-255 (i.e. 8 bit) and 0-65535 (i.e. 16 bit).
Microcontrollers have a limited variable space and this setting gives you some control over how the space is used. Mostly variables will default to 0-255 which maximises the number of variables you can use, but in some cases you may need a larger value range. In particular, the random statement expects its destination to be a 16 bit variable.