The 'Set text size' command only works if you use the 'text' command. It has no effect on the 'print' command.
So what you need to do is to do it change the 'print'commands to 'text' commands.
The text command takes three inputs: x position, y position and text$. The text$ is a string so it can't take a numeric variable (like your 'age' variable). What you need to do is change it to a string using the
str$() command.
So instead of:
Print "Glyn you are now ", age
use
Text 0,40,"Glyn you are now "+str$(age)
If you want more info, look in the darkbasic help section for the text command or
go to TDK's tutorials

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