We spoke to pro artists, and these are the tools they use for game art today
For serious 3D modelling, especially for characters and organic objects, you'll want to consider ZBrush, a powerful tool allowing a tactile approach to 3D modelling.
I followed these steps to remove and add objects from a photo using Photoshop's Generative Fill tool
Photoshop's Generative Fill revolutionizes object removal and addition with impressive accuracy and ease, transforming images into new styles with minimal input.