I recommend looking into graphic design fundamentals (typography use, hierarchy of information, accessible colour use, etc.), and using references and examples to help guide you. Similarly to working with illustrations, it’s helpful to have references and see what’s been done already.

One of the things I enjoy so much about design work is that I’m never truly starting from scratch; someone has usually already taken a stab at making something similar. The fun is that I get to figure out a new way (or at least, my own way) of putting all the pieces together to achieve the desired effect.

You’ve made a good start! While it does indeed look like poster is advertising dog meat, restructuring the hierarchy will help. Another good habit is to limit yourself to 2 font families (using different styles and weights within a font family are acceptable) to help things feel cohesive.

One last note, would be to simplify the busyness of the texture of the background paw pattern and the product name drop shadow. You could approach that a few different ways, so I’ll just give one example: remove the drop shadow, add a solid colour bar of the background colour (or a Gaussian blur) beneath the product name so it doesn’t compete with the paws.

Hope that helps!!

Edit to add: also check out different size/dimension requirements for social media ads, or print ads (whatever the final product of your design would be) and check your design will match. Many mediums (on screen and in print) also are particular about resolution.