There are four key elements that you will need to set up an e-Commerce business.
Company website - this will allow shoppers to browse and purchase the products or services they want to buy
Payment Gateway - this is connected to your website and securely sends online payments for authorisation to your acquiring bank
Merchant Account - is a bank account specifically to receive the funds you accept online and is completely separate from your normal business bank account
Business Bank Account - this is where the funds from your merchant account will be transferred to on a regular basis for you to then use for your business
All of these services can be supplied by varying companies, and you will find that some suppliers offer more than one of these services, which will help with set-up time and reduce running cost and hassle once your service is set up.
Look out for providers who offer more than one of these services as this will save you valuable time and money when setting up and running your business.