Any kinds of opinion are welcome.
When you will be a Master Player

What is master level?
You forget an important thing: Play alot of strong tournaments (regular time control)

I think he means FIDE master, and to answer your question for me it's a complete mastery of practical endgames and theoretical rook endings and pawn endings. That involves:
-Reading through Shereshevsky's Endgame Strategy again and How to Play Chess Endgames a few times.
-Reading through Dvoretsky's Endgame Manual, Survival Guide to Rook Endings, Secrets of Pawn Endings, Smyslov's Endgame Virtuoso, and the appropriate CCE and ECE volumes a few times ensuring I reinforce anything I may have missed. Or repeat certain positions a few times like I did when going through Basic Chess Endings (even Benko's revised edition has some errors but is overall good.)

When will I be a master player ?
The clear answer is: never.
Games need to feel like games to me, studying games feels too much like work. I just play to have fun.

@ viktor, what will you do with tournament without skill and knowledge?
will you learn by mistake in tournament - then repair, mistake -repair, mistake-repair?
one day you will discover that you are too old to play and old mistakes will be redone again.

Never. And 2000 opening lines isn't too much for the human's memory? Even for grandmasters?
Nope

I think he means FIDE master, and to answer your question for me it's a complete mastery of practical endgames and theoretical rook endings and pawn endings. That involves:
-Reading through Shereshevsky's Endgame Strategy again and How to Play Chess Endgames a few times.
-Reading through Dvoretsky's Endgame Manual, Survival Guide to Rook Endings, Secrets of Pawn Endings, Smyslov's Endgame Virtuoso, and the appropriate CCE and ECE volumes a few times ensuring I reinforce anything I may have missed. Or repeat certain positions a few times like I did when going through Basic Chess Endings (even Benko's revised edition has some errors but is overall good.)
Endgame, !!!
Before endgame, strong payer will slay you in middle game

When will I be a master player ?
The clear answer is: never.
Games need to feel like games to me, studying games feels too much like work. I just play to have fun.
without input output is zero. First eat, then fight.
proper and attractive studying method will help you lot.

I've already learned that in the middlegame one should compose a plan in critical positions and the positional imbalances.

And how much do you think all this will take ? My opinion is about 15 years or more
10 or less than 10 years

I've already learned that in the middlegame one should compose a plan in critical positions and the positional imbalances.
That's good

I think you should take a zero from all the numbers and ull still become a master level player
How ? By lamp of Aladdin?

When will I be a master player ?
Games need to feel like games to me, studying games feels too much like work. I just play to have fun.
When u'll start to lose , u no longer find it funny.

When will I be a master player ?
Games need to feel like games to me, studying games feels too much like work. I just play to have fun.
When u'll start to lose , u no longer find it funny.
I loose all the times yet I find it always funny, for some people like me chess is just a time pass not something that a defeat in it will disheart me. I always admire my opponent whenever I am outplayed , the same way I feel pretty cool when I outplay my opponent.

On a side not I personally feel that it is the middle game which determines who is going to win or loose.

When will I be a master player ?
Games need to feel like games to me, studying games feels too much like work. I just play to have fun.
When u'll start to lose , u no longer find it funny.
I loose all the times yet I find it always funny, for some people like me chess is just a time pass not something that a defeat in it will disheart me. I always admire my opponent whenever I am outplayed , the same way I feel pretty cool when I outplay my opponent.
you get fun from losing !!!??
when people will reject to play with a poor rated player , u'll not find it funny (don't mind please).
Moreover how can one get too much fun without having contest and hard competition?
It is not easy to become a master level player in all kinds of chess format. Becoming the stronger master is much more tough. But only two things will make you reached that level.
The contents to be practised ----
Please do not be bothered, it will strengthen you in all kinds of chess format and your ability to quick calculation will be enhanced. After doing that you can challenge any player on earth in any format.