需要网址导航​​从DropDown值onClick按钮传递网址变量

If I submit Go Button Without Selecting it will goto url like This.."&age=10". I need code for navigate to url with post url variable for my wordpress site.

You have 2 options:

1. Use the button to submit a form. Your form should have method="POST".

   <form action="yoururl" method="POST">
       <input name="age" type="text">
       <button type="submit">Go</button>
   </form>
   

2. Use ajax to perform a POST. Here are the docs: https://api.jquery.com/jquery.post/

And here's a quick snippet:

$.ajax({
  type: "POST",
  url: url,
  data: data,
  success: success,
  dataType: dataType
});

For future reference, you should probably post what you've tried and some of your existing code to get quicker/better help from stackoverflow.