How can I edit the size of a report within an email template?

I need to enlarge a report within an email that I am sending through copilot. The text currently stretches across the entire email while the report only takes up about half the email width. I have zero experience in HTML, but I believe that is where I can make the necessary change. Can someone help me identify which element on which line I need to edit? or even just point me to a good HTML learning resource?

I believe this is the section of code I'll be looking in:

  <div style="box-sizing: border-box; padding-top: 0px; padding-bottom: 0px; margin: 0px;">    </div>
    <img alt="" width="580" src="cid:905a5f60-f92c-4b16-a6fd-0cd1c477dcd2" style="border: 0px; box-sizing: border-box; vertical-align: middle;">
    <div style="box-sizing: border-box; padding-top: 0px; padding-bottom: 0px; margin: 0px;">
    </div>
  </div>
  <div style="box-sizing: border-box; padding-top: 0px; padding-bottom: 0px; margin: 0px;" >
    <br style="box-sizing: border-box;">
  </div>
  <div style="box-sizing: border-box; padding-top: 0px; padding-bottom: 0px; margin: 0px;" >
    <br style="box-sizing: border-box;">
  </div>
</div>