I think it depends on what type of art/photography/film you make and where you want to exhibit it.
In the UK there are websites like https://www.a-n.co.uk/news/ and http://www.artsjobs.org.uk/artsjobshome/ which list exhibiting opportunities.
For many of the galleries I’ve worked with and at the work they exhibt is mostly concept driven, so definitely make sure you can exaplin your work and general practice in a way that relate to the themes of the gallery/exhibition. Of course the work should look “nice” but it’s not the most important thing.
There is also the commercial art world but i have less experience of this.