The correct HTML for adding a background color to a web page is as follows:
<body>
Where "#colorcode" should be replaced with the desired color code, which can be in the form of a Hex code, RGB, RGBA or HSL.
For example, if you want to set the background color to red, the HTML would look like this:
<body>
You could also use the hex code for red:
<body>
You can also use RGB,RGBA or HSL.
<body>
<body>
<body>
Note that you can also use CSS file to set the background color of the body, instead of using the "style" attribute in the HTML.