I am still confused if Destiel is canon or not because one side says yes and the other no
It isn't canon.
The love confession wasn't reciprocated by Dean, per the script, Jensen, writers, even Misha has admitted that. There can't be a relationship when only one side feels that way.
Destiel can't be canon because Dean isn't in love with Cas. No matter what people have said in fanfic, no matter how much explicit fan art they create, the canon is that Dean is a straight man who hunts monsters, not marries them. The debate over if Castiel can even feel or understand love is a whole other question, but Dean's position already rules it.
Dean saw Cas as a brother in arms, someone he fought battles with, not a lover. He states multiple times that he is straight and he only ever shows interest in women. He's also only into humans. Human women. Castiel as we knew him in Jimmy's body isn't a woman, and even if he wasn't in a male vessel he's still not a human. Cas could be wearing the bustiest Asian beauty Dean's ever seen, but that won't make him Dean's type.
The evidence that is used to say it's canon is based on things like coloured lights or what Dean's eating. Most of it the evidence is made from compilations of clips or gifs by people who aren't able to have real discussions about the show because they haven't actually watched it. These gifs of "loving looks" are often poorly chosen, since they accidentally include times that Dean was looking at Sam. See what I mean about them not having watched the show?
There are people who have been told to skip the first three seasons because it's only worth watching Supernatural for Destiel. Even Misha has told people to do this, but he also makes money from shippers which is why he panders so much. The show was about two brothers, and the main draw is always going to be the two brothers. Destiel gives him an in, a way to get attention on himself.
So, no. Destiel isn't canon.
It's a one sided crush.
In the words of Jensen Ackles himself:
