The camera is a huge part of this film. It is a character in itself, in a sense. It is motivated by what type of movie this is. The film is expressionistic and about Lionel- a creative. The camera is to Scorsese as the paintbrush is to Lionel in a way. Even without this film in mind, many people consider Martin Scorsese to be a an utter visionary with the way he uses camera in his storytelling. Lionel gets these bouts of creativity which he tries to attain through having a muse. The camera taps into this and is expressionistic and majestical in a sense as well. There is a lot of movement as Lionel himself- or at least the way we see him and his world is like this. It is actually when shots are static that they become tense because the precedent for it makes it seem weird. An example of one of the strongest moments of the camera work, in my opinion, is when Lionel is actually in the act of creating or at least about to create- and just as Lionel is hit with a wave of inspiration, the camera surges forward into him like a rush of (expressionistic) creativity. This camera and style continues throughout the film and is almost like a motif in the film.
The colors of the film are a big part of it as well, which makes sense because it is a very colorful film as in it is about painting. The whole world is the artistic world, so through comparing colors of different characters, times, and places, Martin Scorsese impresses various moods and feelings upon the film. At the beginning of the film, when everything is seemingly alright within Lionel and his muse (or at least not as bad as it gets in the end), the colors are more primary ones. However, as the film progresses, the color palette becomes a darker more mundane one as his relationship with his muse deteriorates. His muse's clothing as well is a big indicator of this as well. At first, she wears more natural and normal colored clothes. However, by the end, she wears a pure black dress. She has become this person completely dark and void of life in a way near the end.
Just like Lionel, Scorsese himself has his own color palette consisting of camera, sound, editing and colors for his work of art, "Life Lessons".