Thank you for the opportunity to help you with your question! I hope that my answer is helpful to you :)
The definition of a gene pool is simply a collection of all genes in a population. It can also be described as the total genetic diversity found within a population or species. The population it is describing can be any population, such as frogs, humans, trees, dogs, ect. The genes it is describing can be anything from freckles, blonde hair, black hair, wings, eye color, skin color, ect.
Please let me know if you need any clarification. I'm always happy to answer your questions. Have a fantastic day!