pass values via URL concerning wordpress?

I want to pass values via URL when a user clicks a specific link I have set up. However, since wordpress uses template files as opposed to a standard page, How do I tell wordpress which URL I want to use?

For example, I have this piece of code set up to display an address from the data base, and is clickable to a specified page. I have tried appending key=value to the end of the address, but It is not yielding results.

here is the code:

?><a href="http://localhost:8888/treehouse_wordpress_custom_theme/?page_id=87"><li style="list-style:none;"><?php
			echo $data->results[0]->formatted_address . "<br>";

I tried appending like this:


The only result I get with this in the URL is:


this is the page id for the wordpress page I am using:
It uses a template file (map-script.php), and everything works as far as that goes. i.e- when a the specified link is clicked, the page gets called and the script is used. Only the values that I am trying to send are not being seen.

I think that ultimately, key=value needs to be sent to the script (template file) I am using for the page (page_id=87).

If that is the case, how would I go about doing that.