If your computer is equipped with a WiFi device and you are in range of a Access Point you just click on your browser icon wait a few seconds whist it communicates with the AP and then you should see a screen similar to the one shown below.
Check the bottom left of the screen if it states "Internet uplink ok" the AP is connected to the World Wide Web.

Then Login using your user name and Password, click enter and you will then be connected to your home page automatically.

In the example below Username and Password have been entered so just click the black enter button on the page and see what happenes

This screen image is from a Laptop running XP Home using Microsoft's Internet Explorer browser, it has 'news.bbc.co.uk' as its home page ,