Final answer:
To start an e-commerce site, one needs a reliable e-commerce platform and a secure payment gateway, along with web hosting, a domain name, inventory management, and digital marketing strategies.
Step-by-step explanation:
If Jain wants to start up his own e-commerce site, two essential items he will need are a reliable e-commerce platform and a secure payment gateway. The e-commerce platform acts as the backbone of the online store, where products are displayed, and transactions take place. Meanwhile, a payment gateway is crucial for processing customer payments and ensuring sensitive data such as credit card information is encrypted and transferred safely over the internet. Beyond these, he should also consider aspects like web hosting, domain name, inventory management, and digital marketing strategies.