A text file doesn’t really have any formatting, or ‘styling’, information. In an ePub you need to provide the styling using a style sheet. CSS (cascading style sheet) contains all the styling information for your book which makes it all pretty when you link it to the html files.
Your code should look something like this:
<p>This is a normal paragraph.</p>
<p>This is a normal paragraph.</p>
<div class=“image”><img alt=“” src=“../Images/touring.jpg”/></div>
<p>This is a normal paragraph.</p>
<p>This is a normal paragraph.</p>
With a styles.css something like this:
p {margin:0; text-indent:1.2em; text-align:left}
div.image {margin:2em auto; width:50%}