You need to first go to places with high quality people with a focus on building a community. From there you have a high chance of making friends. As an adult means heading back to classes. A fitness class, a cooking class, an improv class, etc. Right now the most popular are fitness classes especially for HIIT and running that have a social element like beer or coffee afterwards.
I agree. You won't find someone by just staying home and taping/swiping some dating app.
Actually the dating app could be a good start as it will trigger the initial contact for a first meeting or dating activity.
Back in the days I wasn't really looking for a relationship but I use to go out a lot to different activities either from my group of friends or from a friend of friend. This activity itself will just drag lot of different people together and allow to start connecting with people.
If by chance we see that we were both single it could lead to further one on one meetings and more ...
Back to the dating apps, I was extremely shocked when my coworker having move to Montreal recently has found a girlfriend quite quickly. On the other hand another colleague seems to have more difficulty and even shared the struggles. Like he connected with someone but she refused to discuss further when he replied negatively to being a homeowner.
We even asked the successful colleague how he filled up his profile to finding someone that quick.
Coming to my initial point, it's summer, go out, join the numerous activities Montreal has to offer. And as
@Lunaseraphim said, work on yourself first. Nobody would want to be with someone negative (or maybe if she wants to have an echo chamber to mumble about anything lol).
Enjoy!