how can I start running a small webpage for business?

A commercial website has to be good otherwise it is a waste of time. A good website will cost about £1000 at least and then it needs regular SEO and marketing.

Maybe look at it the other way: how many customers do you need to make reasonable money? Taking a 2% conversion rate you will see how many TARGETTED visitors to your site you wil need. Say this is 200 a day. How much will it cost to make a website + SEO to generate 200 targetted visitors per day? (You need to discuss this with the website designer). Secondly is this economic? Does the cost of SEO, in particular, produce enough in terms of generated sales?

You need to sit down with a web designer who can give you the whole package (design, implementation, SEO, marketing etc.)

What you must not do is try and do this on the cheap (like a template or someone who just designs the site- a website is useless without visitors/SEO).

Starting your own website is a brilliant idea to boost your small business. To create your site you can use a ecommerce site building platform, there are many of them and you can probably find even a free one.

I can suggest you GetSocio.com. This site builder is great for small businesses like yours because it's a readymade solution so you don't need programming skills to make your site and you will have your site up and running almost instantly. The websites on Getsocio are fully hosted so you don't need to look for hosing provider. Payments for your products can be accepted through any of integrated payment gateways, e.g. Authorize.net, PayPal and so on. The prices are affordable. There are 14 days free trial and then you can choose one of pricing plans that starts form $15 per month and 5% transaction fee.

However, you should know that starting your website will not bring you thousands of customers instantly. You will have to put your time and efforts to promote your site to make it popular.