1) I don't remember. If you pick up certain habits like meditation, it becomes easy. It takes time to work but eventually meditation strenghtens your prefrontal cortex and it gives you this iron will and you have much more self-control. I did like 6-7 months at one time
2) It fluctuates. The more you masturbate, the higher your libido ends up becoming. If you don't masturbate for a long time then your libido will drop.
3) No
4) Meditation really.
As for the benefits I don't think long term nofap is beneficial. High libido is what gives you energy, if you don't do anything sexual your libido will drop. Which is why so many nofappers complain about the "flatline" and they think its a symptom of withdrawal from porn. It doesn't work like that, it just doesn't. If it was withdrawal you would feel it very quickly, not weeks after stopping. You get most benefits if you just keep your libido high, so don't masturbate for 3-4 weeks and if you feel your libido is gone then restart.