the same way your learning, by asking questions on free forums, i started out with the beta of XP and a PC world excuse for a 1st PC. since then i have worked in a PC shop, a laptop specialists and had a attempt at running my own business. all without qualifications.
for the next 6 weeks im off to retrain for maintenance on IT related peripherals, ir printers, projectors. it will be the 1st qualification i had since school and the NVQ's i got soon after.
you get help, warnings and links to plenty of how to guides. only thing i can advice is asking your old man if the PC is covered under house insurance on the off chance something goes wrong