First of all, please learn how to take a screen shot (Do not use a camera). Search on this forum or on Google for “How to take a Screen Shot” (it involves the PrtScr button).
Text sizes are dicated by the font used by your printer.
Printer tags such as <L00> will print the font as the standard size of your font, where as <L11> would print the text with double height and double width.
Some printers allow you to send special commands to them using the <XCT> tag. But these printers typically use the ESC/POS protocol (which your printer doesn’t appear to use).
If you do have a printer that supports ESC/POS then you can send an XCT command to tell the printer to start using a different font mid-way through your ticket. For me, the command I need to use is:
-- Small font
<XCT>27,77,1
<L00>I am small text
-- Regular font
<XCT>27,77,0
<L00>I am regular text
<L11>I am large text