This one is a mix of posters from freepik.com and one of Ben Marriot's lessons on textures (links are below) made just to learn, in fact, textures, designing posters and just for fun.

Credits: 

Poster reference: https://www.freepik.com/premium-vector/creative-exhibition-flyer-poster-concepts-with-abstract-geometric-shapes-human-silhouettes_30164160.htm

Cow: https://youtu.be/httMaxrBNtk?si=JJ5eHoVGmkyXpN_B

Mockup: someone very talented, sorry, I lost the link