Not completely sure what to advise I’m afraid.
I did some web work back in uni, but I wouldn’t know the best places to look for tutorials on the web, but that is exactly what I would do. Start with the web, just google and find a tutorial site that you feel comfortable with, some will be good, some bad, but I can’t point you to a good one I’m afraid.
Start with HTML, should be pretty simple and upgrade so you are talking about using CSS and stylesheets ( pretty much the standard today ).
After that, its all down to what you want to develop. PHP, Python, Javascript are things you might want to look at, some SQL for database queries if thats what you need.
1) Yes, there are free online resources. Google is your best friend
2) HTML / CSS…then go on to the scripting side of things.
Sorry, can’t be more help, it’s been a while since I’d done any web based stuff.