You have to find a free web host, if you do not own a server.
Web hosts will usually provide you with tools on starting your website. Most of them use HTML or a variant of HTML. Others will allow you to modify only the body tag or a certain div in it while others may allow editing of the whole HTML document. Whichever case, you will have to learn how to construct web pages using HTML.
Other web hosts will want to use other markup language, e.g. wiki markup, in which case you'll have to learn that separately.
Most if not all free web hosts will not provide you full control of your web site, e.g. using a programming language such as PHP or using databases.
If you do not want to learn neither html nor php nor any other programming language you should get a cheap webhost for about 5Euros a month. check webhostlist.com. the offer shoold include mysql-database support, at least 100mb of webspace. than you can install a CMS-system which is the easiest way to start a website. Check www.joomla.org. the community there gets you started easily. Easier then learning html or anything else trust me! And an easy way to make a really professional website. The software is free but you would need a webhost that supports a mysql-database and those offers are usually not available on free webspace.