Just got the privilege to protect answers however I'm not quite confident with it yet.
Could anyone let me know when should one protect a question?
Short answer: please don't. Leave it to the mods.
Edit:
Here's my reasoning - this site is under a lot of scrutiny. Since Mage Stack Day I have had 15 or so people contact me and say that they feel this isn't a very open or accepting place for newcomers.
A protect on a question or answer would only be used properly in the case of dozens of duplicate answers or a question that is being repeatedly edited.
In an effort to keep these complaints down let us be the bad guys when we have to be - and we'll try not to be - and you keep doing what you're doing.
Some reading about when to protect:
https://meta.stackexchange.com/a/52765/157698
From the article:
When should I protect or unprotect a question?
Do protect questions that are attracting a lot of non-answers or very poor answers (spam, etc.) from new users. Don’t protect questions just because they’re linked to on a high-traffic news site. Do unprotect questions that aren’t currently attracting a lot of attention and don’t have a long history of unproductive answers.