I have 3 questions

1
1) How to study openings.
A) Going through DVD
B) Going through chess book
C) Watching basic video from youtube

2) I have been analyzing my lost games here on lichess.org using stockfish.
when stock fish says +1 , does that means it's easy winning chance for other player or still requires lot of precise moves

3) How to think and make a move
A) Do you check all things before making a move like, what threat, open lines, diagonals, pawn structure, tactics, prophalyxis
B) Is it all just pattern recognition and intuition
C) or some specific method is there

Thank you

1. C
2. when stockfish says +1 it means that White has good winning chances
3. A

1.B with engine (books may contain errors )
2. +1 = equal to 1 pawn advantage. Easy win depends on rating level.
3.A. switch to B after some 1500 games.