Of course, you don't have to do it this way - there are plenty of programs around that will write your HTML for you.
If you just want to turn a document into a webpage PDQ and you don't much care how, your word processor, such as Microsoft Word (or desktop publisher, such as Microsoft Publisher), can probably do it for you. There should be a "Save As HTML" option on the File menu : load up your document and select that option. It will create a text file with the extension .htm or .html (which tells Windows to treat it as a webpage), with all the necessary tags to format it like your document - more or less. If there are pictures embedded in your document, it will also create a separate file for each one, called something like image1.gif, image2.jpg etc. To see what your new webpage looks like in the web browser, just double-click the .html (or .htm) file from Windows Explorer or My Computer. and there it is. Easy.
So why doesn't everyone just do that? Well, Word for example writes horrible, messy HTML, with literally hundreds of extra codes you don't need cluttering up the place, which makes it slower to load (and much harder to read). Worse, Word's HTML version of your document is often not quite the same as the printed version - all sorts of things don't translate very well. And there are lots of things you can do in HTML that you can't in a ordinary document : make links to other pages, play sounds or animations, and all sorts of other useful tricks.
Having said that, one thing Word does translate into HTML rather well is tables. So if you want to display information in a table, an easy way to do it is to create the table in Word, and then use Word's "Save as HTML" feature. Once it has turned your table into HTML, you can edit the HTML document as you would any other HTML document, and add any pictures, links or whatever it your page requires. To see an example of a Word-generated HTML table, see the dictionary of computer jargon.
There are plenty of specialised webpage-makers on the market, and indeed on the internet. They range from a total WYSIWYG approach, where you point and click and select from menus and the program writes all the code, to a sort of "Notepad with extras" approach, where you write the code but the program helps.
Top of the range is the professional's web page editor DreamWeaver, from Macromedia, which will do practically everything but put out the cat (or write the text, which is always the hardest bit). Unfortunately, it will also set you back several hundred pounds (or dollars). Dreamweaver is absolutely fantastic, and worth every penny if you can afford it. But you can create a perfectly good site without it. My advice, for all computer purchases come to that, is don't spend the money until you can explain why you need to.
But anyway, there are literally hundreds of other webpage makers, at all prices including completely free. For example, this page was created using an excellent free webpage editor called Arachnophilia, which is the "Notepad with extras" type, available from http://www.arachnoid.com. I used it for this website mainly because it's a nuisance displaying the < and > symbols on a webpage using Notepad - you have to type in a string of 4 symbols in order to display them, rather than have them interpreted as the beginning or end of a tag. But Arachnophilia has quite a few other useful features too, like highlighting tags in a different colour, and detecting if you accidentally fail to close a tag with >, and I shall probably continue to use it after I finish this site.
But Windows Notepad really will do almost as well, for most purposes - I've written most of my pages that way. For example, www.jonstorm.com was all written in Notepad. And I find I still tend to use it if I just want to make one or two quick changes.
Another thing you are going to need if you do much web design is a decent graphics package. If you have a scanner it almost certainly came with one included, which should do to get you going. Windows Paint, free with Windows 95 and 98, is no use at all I'm afraid, as it can't do JPGs or GIFs (the best Web graphics formats). Professionals tend to use either Adobe Photoshop or Macromedia's Fireworks, both of which have many wondrous features but cost lots of money. I have tried both, and while what they can do is pretty impressive, neither is particularly friendly for a beginner. You tend to spend most of your time looking for the feature you want amongst a million other features you don't, rather than actually creating anything. Great if you already know a bit about graphics, not so great if you don't.
The best of the rest is Paintshop Pro, from Jasc software. You can download a trial version, or look around on the internet for an older version that is now freeware. I find it much more intuitive than Photoshop, if not quite as powerful. Not a bad place to start. But have a look around, there are loads of different packages out there. If you have a digital camera, you probably got a basic graphics package free with it. My favourite basic package is ACDSee from ACD Systems, a terrific image browser/viewer with a basic editor built in, perfect if you just want to tweak a picture's size and JPEG compression settings, or convert a TIF or whatever to JPEG.