The screenshot of the tutorial , was shown only for general understanding, where the information was taken from while adding the resource to the game.
gui/summary
is the folders in the mod the full path may look like this:
summary.js file
/home/.local/share/0ad/mods/Name of your mod/gui/summary/summary.js
var g_MaxHeadingTitle = 9; replace the value with 10 (if 1 new resource is added)
summary.xml file
/home/.local/share/0ad/mods/Name of your mod/gui/summary/summary.xml
<repeat var=“x” count=“9”> replace value by 10(if 1 new resource is added)
there are 5 such lines in the file