If when you first post your question you click the email check box, you will get an email every time somebody responds to your question. As for a liked comment I not sure what you mean. A like is just a check box not a comment or a reply. Comments are typically wall posts and you can respond to them from your home page or on the wall of somebody else.
To post a question to the network, you post it from the Questions tab. To post it on your own page, your post it from the Home tab.