completely varies, some days its 1min others its half an hour or an hour

I think it can vary, we have to go to sleep school during the first year.

My little boy settles almost instantly now, but it wasn’t always like that. I believe in teaching babies to self soothe, it helps immensely in routine and as they get older too. The way to do it is by placing them in their bed fully awake, then quietly tapping the mattress behind their head, shooshing and gentle touches. If baby doesn’t seem to be settling after a few minutes of doing this, quietly leave the room and come back in 10 minutes if baby is still awake. Continue to repeat the process lengthening your time away if necessary or if baby is quietening down. This method will take a few weeks to reap real rewards but it is worthwhile! Neither of my kids wake up in the night and both can be placed straight to bed with no crying and they just curl up and sleep.
A nice bedtime story before bed as part of the routine is also very good in settling them, and also if you can play some white noise too.

I never went into rocking my youngest asleep or let her fall asleep on me, just because you create kids becoming dependent of you in this way.

All babies differ. My eldest was took quite some time to settle herself. My boy was never able to sleep much during the day (not more then 5 minutes) but settled well for the night. With my youngest I learnt my lesson and put her always awake in bed and let her settle herself which she did within 1-10 minutes.