下拉菜单。 完全初学者,超出我的深度,救我[关闭]

so I am trying to edit my website to include a drop down menu. I have created the drop down but I need to link it so that when I click the 'add to cart' button (which redirects to a checkout), the option selected is remembered so I can see it. Really looking for a place to start since im a bit lost beyond this point. Thanks in advance

<form action="/action_page.php">   
<select>
<option value="Childrens Small">Childrens Small</option>
<option value="Childrens Medium">Childrens Medium</option>
<option value="Childrens Large">Childrens Large</option>
<option value="Adult Small">Adult Small</option>
<option value="Adult Medium">Adult Medium</option>
<option value="Adult Large">Adult Large</option>
</select>
</form> 

Your HTML would look like this:

<form action="/action_page.php" method="post">   
<select name="size_selected">
<option value="Childrens Small">Childrens Small</option>
<option value="Childrens Medium">Childrens Medium</option>
<option value="Childrens Large">Childrens Large</option>
<option value="Adult Small">Adult Small</option>
<option value="Adult Medium">Adult Medium</option>
<option value="Adult Large">Adult Large</option>
</select>
</form>

In your PHP program you would then refer to the value selected as $_POST['size_selected'] (or whatever you named the select field using name="").

If you prefer using GET. Then change the method to method="get" and refer to the value as "$_GET['size_selected']