If you want to have some fun without the worries about wrecking anything in the house, go down to your local Bunnings and grab an external tap, one that includes all your valves and washes. Take it apart bit by bit. You will get to see where the washer sits the valve and the pressure it takes to undo and do the parts up.
I found this helpful years ago because the principles are almost exact with internal and external taps and shower head replacement of valves and washes.
And I know people hammer YouTube a lot but for learning how to do minor repairs it’s great. - gippslandhome
Some TAFEs offer intro courses to plumbing which teach you the basics. - ProjectPete
A lot depends on where you live. Queensland is the most strict I think, you can change a tap washer and that is about it. In SA, TAFE has a basic home and building maintenance course that runs for 10 weeks at a cost of $520. - Brad