Social networks for developers?

I'm doing some research to see what I'll have to study to re-enter the website development market. I have been out of the market for 15 years. The last time I used the notebook to write HTML and CSS, I know that many things have changed. Can someone direct me in a good direction so I can ask the right people questions about how much education I will need to succeed in this business again? Thank you in advance for your response and consideration