The radius of your business on Google My Business (GMB) is determined by the location of your business and the area you want to target with your services or products. By default, Google will automatically set a radius around your business based on the location you've provided when you set up your GMB profile. However, you can also edit this radius to reflect the area you want to target. The maximum radius you can set for your business on GMB is around 50-70km. However, setting such a wide radius is not recommended, as it may not be relevant to your customers. Instead, you should focus on targeting a radius that makes sense for your business and customers. For example, if your business is a local cafe, you should target a radius of around 2-5km because this is where most of your potential customers will be. But you might want to target a larger radius if you're running a service business that travels to the customer's locations. Keep in mind that even though you can set a radius, it's not a guarantee that your business will show up in search results within that area, as the ranking of your business in search results is determined by a variety of factors such as the relevance and popularity of your business, the keywords used in your listing, and the reviews and ratings of your business.