Change your gui code as follows
GUI.Label(Rect(430,320,500,500),"<color=green><size=100>Win</size></color>"); GUI.Label(Rect(400,470,500,500),"<color=green><size=35>Your scores : </size></color>"+"<color=black><size=35>"+player_script.points+"</size></color>");
also, if you want to change the font type, you can try this rich tag and let me know if it worked
<font face="verdana">....</font>
elie111
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