I want to set App icon on dashboard. Then i click on sale App icon then redirect on sale Form.
You must to specify the icon file in your module menu definitios as:
<menuitem name="mymenuname" id="myid" web_icon="mymodulename,static/src/img/app_icon.png"/>
Or you can specify the icon file in the menu definition on Odoo.
Here you can generate icons: https://spilymp.github.io/ibo/