Frankly, it’s a miracle that Krita exists. Krita is completely free! You can download it for free, and anything you make in it can be sold commercially. Krita is free Photoshop is a $19.99+ monthly subscription
Now let's get started on the long answer, beginning with a lovely table comparing the features of Krita against Photoshop.
Photoshop is probably better for those with plans to become professional artists, but in that case there’s also no harm in starting with Krita and transitioning to Photoshop once you start getting commissions. Here’s the short: Krita is better for hobbyist artists who just want to draw and paint digitally. Unlike Krita, it was not designed with digital drawing and painting as its primary purpose, but it is such a versatile piece of software with such a broad set of tools, that digital painting is just one of the many things that can be done with it. Photoshop, on the other hand, has set the benchmark for digital image creation for decades. Developed by artists themselves, Krita provides a more streamlined set of tools and features that cater specifically to digital artists. Krita is a powerful (and free) digital painting software designed for artists, illustrators, and animators. Compared to Photoshop, Krita is one of the new kids on the block.