Dear god what is with all the 's (btw none of that code is relevant from what i can tell), since this is HTML in order to do a line break you need to add
"hello world this
this is a test article".
To get this format to look like this in HTML you would do
"hello world this <br />
this is a test article".
Tah dah
However you specifically say "Textbox". In html, a textbox (input type="text") is a single line input, I think what you are looking for is a text area.
<textarea style="width:400;">
"hello world this
this is a test article".
</textarea>
By using a text area you could simply type your content in as is and it would show as desired.
Or you could use the <pre> element as well.
<pre>
"hello world this
this is a test article".
</pre>