there are lot of high quality free videos on youtube in which you can learn openings.
How to study openings?

Everyone talks about studying openings, but what is actually the best way to do so (for free even maybe)?
Picking up a book/e-book?
And if so, can good literature on openings be found for free?
Looking at games at a database?
Propably not...
thanks in advance!
Youre losing to 800 players in 11 moves. Opening study is the last thing you need. What you need now is Opening Principles:
1. Control the center.
2. Develop minor pieces toward the center.
3. Castle.
4. Connect your rooks.
Tactics...tactics...tactics...

Diakonia is right.
And even when you do get high enough, free U-Tube videos are utter garbage. Much of the analysis is bad or even outright wrong!
You get what you pay for.
What you should be doing is studying endgames right now, followed by tactics. Don't be going for free garbage. Invest in a couple of books (Amazon sells most at a discount), and get out a 3-D board with pieces. Don't go with e-books or videos. Both result in passive learning, and you don't get anywhere. You need to have a board out with pieces when studying for it to be truly effective.

You need almost no opening knowledge to reach a decent rating, follow Diakonias advice. But I disagree with ThrillerFan, you can find good opening videos (nothing detailed, just general plans) in youtube IMO, at least that is the way I learned.
"If you want to play chess competitively, then you must develop an opening repertoire." - GM Patrick Wolff (1997)
For someone seeking help with choosing openings, I usually bring up Openings for Amateurs by Pete Tamburro (2014).
http://kenilworthian.blogspot.com/2014/05/review-of-pete-tamburros-openings-for.html
I believe that it is possible to see a fair portion of the beginning of Tamburro's book by going to the Mongoose Press site. Perhaps comva would also want to look at Discovering Chess Openings by GM Johm Emms (2006).
https://web.archive.org/web/20140627114655/http://www.chesscafe.com/text/hansen91.pdf
"Each player should choose an opening that attracts him. Some players are looking for a gambit as White, others for Black gambits. Many players that are starting out (or have bad memories) want to avoid mainstream systems, others want dynamic openings, and others want calm positional pathways. It’s all about personal taste and personal need.
For example, if you feel you’re poor at tactics you can choose a quiet positional opening (trying to hide from your weakness and just play chess), or seek more dynamic openings that engender lots of tactics and sacrifices (this might lead to more losses but, over time, will improve your tactical skills and make you stronger)." - IM Jeremy Silman (January 28, 2016)

I don't. What's the point in playing something everyone is brave at. The most popular response to e4.
"One of my main aims was to give the reader enough confidence to face the unknown; to be able to play good, logical moves in the opening despite in many cases having a lack of concrete knowledge of the theory." - GM John Emms in his 2006 introduction to basic opening principles, Discovering Chess Openings
In a 2006 GM John Nunn book, in connection with opening study, it is stated that, if a "book contains illustrative games, it is worth playing these over first".
"... I feel that the main reasons to buy an opening book are to give a good overview of the opening, and to explain general plans and ideas. ..." - GM John Nunn (2006)

Everyone talks about studying openings, but what is actually the best way to do so (for free even maybe)?
Picking up a book/e-book?
And if so, can good literature on openings be found for free?
Looking at games at a database?
Propably not...
thanks in advance!
The best way is probably to analyze with a strong player who has experience with the opening himself
If you insist on "studying" openings, play as many games as you can with the ones you choose
Great advice. I never learn openings as well as I do when I experience them in a game. Even if I study a certain line, chances are I will forget it when it comes time to play it. You will make mistakes; learn from your mistakes. Once I make a mistake in an opening, I remember what not to do far better than I would from studying openings.
In one of his books about an opening, GM Nigel Davies wrote (2005), "The way I suggest you study this book is to play through the main games once, relatively quickly, and then start playing the variation in actual games. Playing an opening in real games is of vital importance - without this kind of live practice it is impossible to get a 'feel' for the kind of game it leads to. There is time enough later for involvement with the details, after playing your games it is good to look up the line."
Everyone talks about studying openings, but what is actually the best way to do so (for free even maybe)?
Picking up a book/e-book?
And if so, can good literature on openings be found for free?
Looking at games at a database?
Propably not...
thanks in advance!