This importance of music to create content is mainly based on EMOTIONS, that is, on the emotion that the viewer wants to emphasize. In such a way that if your video is about funny pets, it is best to resort to allusive music with comedy, which would also be good for a video about jokes.
On the other hand, if you are one of those who seeks to transmit an inspiring message, who looks for ways to encourage people, you can resort to motivating music, with soft and bright sounds that are “in tune” with your message and that literally make “bristle” of emotion to the viewer.
In the movies there are many examples in films whose soundtracks became “cult” as much as the titles they evoke, even going so far as to surpass in some cases, the simplicity of their arguments. A case that personally can exemplify this is ROCKY I, it is an unpretentious story with a masterful soundtrack.
In our case, whose main artistic work is theater; music and sound effects allow us to transmit a clear message to the audience through our works.
Where to find music to create content
There are many sites where you can find and download completely free music tracks that you can use without Copyright and one of these sites is a Youtube Channel called Audio Library Collection, and best of all, every day new tracks are uploaded to which you can access without restriction. There you will find all genres: Rap, electronic, pop, rock, country, children’s, etc.