AWS Website Staging Environment Setup

I need a fully-functioning staging environment for my website built inside AWS. The goal is to let me test new features safely before they ever reach production, so the staging copy must mirror the live site in look, performance, and basic integrations... (Budget: ₹600 - ₹1500 INR, Jobs: Amazon Web Services, AWS Lambda, Continuous Integration, Git, Linux, PHP, Web Development, Web Security)