Technical SEO Boost for ESTA Site

I’ve just launched an online ESTA application service and now I need it to load fast, look perfect on every screen, and get crawled effortlessly by Google, Bing, and even AI-powered tools like ChatGPT... (Budget: $30 - $250 USD, Jobs: Google Analytics, GTmetrix, HTML, PHP, SEO, Web Development, Website Accessibility, Website Analytics, Website Optimization, XML)