I've been working with Dovahzul on an almost daily basis for 2+ years now, so it's hard to give an exact estimate. The good news is that the core, canon vocabulary consists of ~600 words, which can probably be learned in a few weeks of study and practice. And of those 600, you may only use 300-400 in the majority of conversations.

I'd recommend taking a look at the Memrise course to start with. Try your hand at a few of the lessons until you have a good sense of how long it might take you to memorize some of the vocabulary. Practice is key!

Depends on learning speed and ability, also time studied, it's impossible for me to give an answer but it took me about a year of on-off learning. 

I just started, but I can already tell that it's going to be hard. It was a bit confusing at first but it's very fun to learn!

A late response but - how long it takes you to learn a language is determined by maaaany factors.

The most important is your definition of "learn" - being able to understand conversation? Being able to have fluent conversation? Being able to read ion the language? if you aim for flawless mastery you will NEVER achieve it ^^ Not even in yoru mothertongue.

The next one would be your mothertongue - if your mothertongue belongs to the same language family as the language you want to learn you basicly have a huge advantage. As example learning Korean if you are japanese is piece of cake and you can learn it in less than 200 hours. if you are english and try to learn Korean, 2000 hours is more likely.

For Dovahzul you are kinda lucky as it is quite similiar to germanic languages in its structure and concepts. The words will be very unfamiliar but you will get the basic idea quite quickly. i would estimate you would need about 600 hours invested to become able to have fluent conversation in Dovahzul if you are speaking english well. Which btw is not much. Most languages start out with 1200 hours and the most difficult take about 2500 - 3000 hours to learn.

But how usefull one hour of learning is ofc depends on the method you are using so...time may vary.

I think it depends on the ability to absorb, hard work, perseverance and even a little talent. That is why learning and mastering a new foreign language will take a different amount of time for each person. Besides, I also want to introduce to you basketball stars unblocked, a top entertainment game.