How do I make higher quality videos? Mine get blurry and pixelated

Just wondering what I'm doing wrong, I've used comfyui for image generation for some time now and I think I'm getting the hang of it, but video is a different beast, and figuring out myself is a hard process when videos can take 20m to get processed with a 5080, low quality test ones don't really address what I'm trying to fix so I often need to render higher resolutions. Here's an example: The video looks blurry, pixelated and loses detail I was also trying to create a static image of the caracter with slight movement on heir hair, maybe clothes, clouds, etc.