I deployed my website and it contains an API that will not work and in console, it shows some error but the site will work properly in my localhost.
error: Mixed Content: The page at 'index.html' was loaded over HTTPS, but requested an insecure XMLHttpRequest endpoint ---"URL". This request has been blocked; the content must be served over HTTPS.
This means that you accessed your website using HTTPS, but when you XMLHttpRequest, you're using HTTP in that code. It would be helpful to see that code. If you're using XMLHttpRequest like this: http://example.com/, change it to: https://example.com/. This error means you need to use all HTTPS or all HTTP.
Edit: According to another StackOverflow post, you should actually leave out the http/https completely:
//example.com/