Need a Simple payment gateway made form this api

Note: Stay within budget and read everything and look at links below I need a simple API or WordPress plugin built that works with WordPress screenshots of mockup will be provided I am looking to add this API to my checking out screen on WordPress I have posted before but I don't think anyone understood what I am asking for. page 1. 2 buttons on the first page with a label with some text. page2. has one button with a label with text and strings and a button that says pay now it also has a text box that where users enter the username page 2 will verify the username and payment amount in the current when the user clicks pay now it will check and see if the payment amount, time of payment, and user are within 3 mins I will provide source code to convert the CRYPTO Coin I am using and the link to the blockchain tracker I will be using API: [login to view URL] Quick Mockups of what it should look like Page1: [login to view URL] Page 2: [login to view URL]