How to embed leaflet map to html page?

I'm new with web developing, and I want to embed a map to my html page.

How I can do this?

I'm using leaflet map generated from QuantumGIS with qgis2leaflet plugins. In the future, I want to show a heat graph in the map that represent population distribution.

this is my html code:

<div class="widget span8">
        <div class="widget-header">
          <i class="icon-map-marker"></i>
          <h5>Map Visualization</h5>
          <div class="widget-buttons">
          </div>
        </div>
        <div class="widget-body clearfix">
          <div style="height:274px;" id="graph" class="widget-analytics-large"></div>
        </div>
      </div>
    </div>