ASP.NET - How to display data quickly from API

I have a hyperlink in my page , when the user clicks on that link ,it fetches the data from API and displays the same in my page. It is talking too much time for fetching and displaying the data.
How can i improve the performance of this?

Then you need to check the API part. The API may be taking more time than the normal. Check the API part and make sure it returns the value as soon as possible.

As you told that you are using data from API, so it depends on API processing how much time it is taking to get data but while reading records try to fetch required data only instead of complete data.

And after getting record bind your control in this block-

if(!IsPostBack)
  {
   Bind data here
   }