Yes, it is generally okay to use brand names in fiction. Many authors do it to add a sense of realism to their stories. For example, if a character is drinking a Coke in a story, it makes the scene more relatable. However, there could be some legal considerations in extreme cases, like if you're using the brand name to slander or mislead consumers in some way. But in normal storytelling, it's a common and accepted practice.
It's okay to use brand names in fiction. Brands are a part of our everyday life, and incorporating them into fictional works can enhance the authenticity of the narrative. For instance, if you're writing a story set in a modern city, having characters use Apple products or drive BMW cars can paint a more vivid picture of the world they inhabit. But be aware that you should use them accurately and in a way that aligns with the brand's image. Also, it's a good idea to double - check if there are any specific rules or restrictions associated with certain brand names, although in most cases, it's not an issue.