Having been in the field for over five years, I have successfully developed and optimized numerous websites on various platforms including WordPress, Prestashop, Wix, and Shopify. Your project requiring customization, enablement of plugins via coding and a keen focus on resemblances to Flipkart in shopping page, Amazon in account and login page, shop, product, login and the cart pages really excites me. I've had experience with similar custoizations yiu need which gives me an edge to acknowledge where the snags may occur.
One distinctive skill i have is optimal. I ensure that websites I develop are designed and optimized with speed in mind which lets them run seamlessly removing any possible nuisances posed by extra plugins. My proeficiency in CSS and HTML would allow me to precisely create that 'sticky mobile' menu you mentioned.
Most importantly i would provide the same sense of quality control that WordPress itself. Trust to abide by industry best practices working within your means and delivering timely results speaks volumes about the value i place on my work which i assure you is at par with industry standard no matter your budget constraints I'll deliver quality results in a way approachable to you as someone new or familiar with Wordpress.I'm confident that our collaboration will lead to a customized website solution that exceeds your expectations.