To ask am I sleep training wrong?

[StandardNameHere]

I'm a single parent, not that it makes a difference but just to add context that I'm doing it solo so another opinion would really help!
My son is now almost 15 months and still isn't a great sleeper. I co slept which wasn't a problem and it worked well for us but a few months ago I slowly started introducing the dreaded cot.
Started by putting him in asleep, then almost asleep and he'd do a few hours in there before I brought him back to bed (so I could get some sleep!)
So where I am now- the last few nights I've been putting him in there awake, just sat there in the dark with him and he has settled and fallen asleep (no crying involved) so that's fine, work in progress.
The bit I'm struggling with- he wakes throughout the night, a lot.
He's not hunrgy, so I don't feed him.
I want him to learn how to self settle. I'm a big softie so I'm not good with the whole leave him cry, I tend to go in and lay him back down then sit with him for a bit until he goes back to sleep, sometimes this is in minutes sometimes not so much!
My question is, am I doing this wrong? Will I be forever going into his room a million times a night or do they have a magic switch and suddenly start sleeping through?