How do I create a field that has a button/label which has a URL. This URL is used to access reports on a site.

The generic format for a Formula Rich text field to make a hyperlink is this

var text URL =   & "url goes here and end with a semi colon";
var text Words=  & " words for the hyperlink go here";

"<a href=" & $URL & ">" & $Words & "</a>"

So i just write the formula in a formula rich text field? 

yes, try it yourself first to just link to say google.com as a hard coded URL and hand coded words like "Search".

Then improve the formula by adding in your URL and the words.

It gives me an error : " Variable declaration must be assigned a valid expression

Please post your code.

 

var text URL =   & "this contains url address to the report";

var text Words=  & " Click here to access Score Card.";

 

"<a href=" & $URL & ">" & $Words & "</a>"

You will need to edit the formula to put in your own words and your own URL to go to.