How do I override an html for font color to what I want?

The CSS would be...

color: green;

... for whatever tag, class, or id you're trying to override.

Remember that in CSS, the closest the information is to the object, the higher priority it has.

The FONT tag should not be used anymore. You should write this instead:

<span style="color: #0000FF">My Green Text</span>

Good luck!

<tag name here>
{
color:#001100;
}

example:
a:link
{
color:#2B8D2B;
}

and you can control the hexadecimal value for sure.

I am assuming you're talking about the background color of your website. If yes, on the CSS file, you will see:

body {background: #fff;}

All you need to do is change '#fff" to the color you want. You can use the color name "green" or if you want a particular green shade, search for the HEX code of the color and enter it in with the "#"