Fill textbox in WEBUI using FM COM_TEXT MAINTAIN

Hi Gurus,

I am a newbie in CRM.

i would like to ask how to fill (by using codes) a textbox in webui using the FM Com_Text_Maintain with a standard text coming from SO10.

is there a general or usual way of doing it?

Requirements:

1. When the user picks "templates" from the drop down list, the system will fill up the textbox with a standard text coming from SO10.

2. The user can edit the the standard text written in the textbox afterwards.

thank you very much