Everybody's different, but for me- first week or two was tough. After that, it got progressively easier. Tried a smoke at a month, just to see, and it wasn't great. Only smoked about half of it, and it gave me a little headache, and the nasty smokiness hung in my mouth and throat for a while. It was kind of like really feeling the poison in them for the first time. Tried again a 3 months, and only got one drag. I'm not sure at what point, but probably after a couple of months, there was no craving for cigarettes- only vapes.
I'd smoked about 45 years, quit multiple times, and always went back, sometimes after months. I loved smoking, but hated being a smoker. But with vaping, I've always felt after the first few weeks, it was so easy it was like cheating. You get all the good parts, without the bad parts.
So just hang in there- vape as much as you want, and don't fear the nic. Use as high a nic level as you need to get through it. Most people reduce after getting over the hump. I haven't reduced that much, but I'm not worried about it. Nic is not the monster it's made out to be, and actually has health benefits. I've only reduced from an initial 18 (that I'd spike up to 24 when having a few beers), down to a consistent 14mg now.