Hi,
First thing I notice is that you didn't list any data database languages that you know?
Get to know either MS SQL or MYSQL, both arguable very similar but do have their differences.
Once you've learnt that hopefully you can "envisage" a database with peoples basic details, linking to extended details, linking to "posts", linking to comments, etc and begin building your relational database.
From there you need to look at dynamically building web pages by pulling data from a database.
I believe JavaScript can do this but I've not had much experience at all with JavaScript, you may want to look at something like PHP or .net
Good luck as this will not be a simple or easy task